2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
This article is all about what AI trends will emerge in the field of creative operations in 2024. All the marketers and brand builders should be aware of these trends for their further use and save themselves some time!
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Applitools
During this webinar, Anand Bagmar demonstrates how AI tools such as ChatGPT can be applied to various stages of the software development life cycle (SDLC) using an eCommerce application case study. Find the on-demand recording and more info at https://applitools.info/b59
Key takeaways:
• Learn how to use ChatGPT to add AI power to your testing and test automation
• Understand the limitations of the technology and where human expertise is crucial
• Gain insight into different AI-based tools
• Adopt AI-based tools to stay relevant and optimize work for developers and testers
* ChatGPT and OpenAI belong to OpenAI, L.L.C.
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
This article is all about what AI trends will emerge in the field of creative operations in 2024. All the marketers and brand builders should be aware of these trends for their further use and save themselves some time!
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
Unlocking the Power of ChatGPT and AI in Testing - A Real-World Look, present...Applitools
During this webinar, Anand Bagmar demonstrates how AI tools such as ChatGPT can be applied to various stages of the software development life cycle (SDLC) using an eCommerce application case study. Find the on-demand recording and more info at https://applitools.info/b59
Key takeaways:
• Learn how to use ChatGPT to add AI power to your testing and test automation
• Understand the limitations of the technology and where human expertise is crucial
• Gain insight into different AI-based tools
• Adopt AI-based tools to stay relevant and optimize work for developers and testers
* ChatGPT and OpenAI belong to OpenAI, L.L.C.
1. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
กิตติพงค์ นิมากร
นักทดลองวิทยาศาสตร์บริการ
kittiphong@tistr.or.th
02-577-9268
October 13, 2015
ศูนย์พัฒนาและวิเคราะห์สมบัติของวัสดุ (ศพว.)
1
2. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
2
Oceanic Steam Navigation Company or White Star Line
9. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
a) In general, can have
6 independent stresses
(3 normal and 3 shear)
acting at a point.
b) Many practical
engineering problems
involve only three
independent stresses –
called plane stress.
c) Stress state for
plane stress can be
summarized on a 2D
element.
Stress States:
Preferred stress element
for 2D stress:
14. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
การทดสอบแรงดึง
การทดสอบแรงดึง เป
็ นรูปแบบการทดสอบความเค้น-
ความเครียดรูปแบบหนึ่งที่ใช้กันแพร่หลาย เพื่อประเมินความ
แข็งแรงของโลหะหรือโลหะผสมด้วยการใช้แรงดึงจนขาดใน
ช่วงเวลาสั้นๆ ด้วยอัตราคงที่
สามารถประเมินสมบัติทางกลที่สาคัญต่อการออกแบบได้หลายค่า
จากการทดสอบแรงดึง โดยอยู่ในรูปของแผนภูมิความสัมพันธ์
ระหว่างความเค้น-ความเครียด (Stress-Strain Diagram)
14
15. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
แผนภูมิความสัมพันธ์ระหว่างความเค้น-ความเครียด (stress-
strain diagram)
15
y
u
pl
แตกหัก
คอคอด
การยืดตัวถาวรแบบ
สม่าเสมอ
Proof stress
o
A
F
area
tion
cross
force
stress =
−
=
sec
,
F
A0
F
การยืดตัวแบบ
ยืดหยุ่น
16. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
เหล็กกล้า
อลูมิเนียม
ความต้านทาน ณ จุดคราก (Yield strength)
16
17. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
มอดุลัสความยืดหยุ่น (Modulus of elasticity)
หนังสือบางเล่มอาจเรียกว่า มอดุลัสของยัง หรือ มอดุลัสความแกร่ง
หรือความแข็งตึง ( Modulus of stiffness, E )
คือ ค่าความต้านทานต่อการเปลี่ยนแปลงรูปร่างของวัสดุเมื่อได้รับ
แรงกระทาสามารถคานวณได้จากความชันของกราฟความเค้นและ
ความเครียดของวัสดุในระยะแรกที่ยังแสดงสมบัติยืดหยุ่น
(Proportional limit, )
pl
17
=
E
Elastic Deformation
18. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
ความต้านทาน ณ จุดคราก (Yield strength)
คือ ความต้านทาน ณ จุดที่วัสดุเปลี่ยนพฤติกรรมการ
แปรรูปแบบยืดหยุ่นไปเป
็ นแบบถาวร เรียก
ปรากฏการณ์นี้ว่า การครากตัว (yielding, )
y
18
Plastic Deformation
yo
yi
19. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
เปอร์เซ็นต์การยืดตัว (Percent elongation)
คือ ปริมาณร้อยละการเปลี่ยนแปลงรูปร่างของ
ชิ้นงานภายใต้แรงดึง เมื่อเทียบกับระยะการวัด
(gage length)
เป
็ นดัชนีบอกถึงความอ่อนตัว (ductility) ของวัสดุ
และความสามารถในการขึ้นรูปของวัสดุได้โดยไม่
แตกหัก
19
%
100
,
=
o
L
L
strain
20. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
เปอร์เซ็นต์การลดลงของพื้นที่หน้าตัด
(Percent Reduction of Area)
%
100
area
of
reduction
%
−
=
o
f
o
A
A
A
เป
็ นดัชนีบอกถึงความอ่อนตัว (ductility) ของวัสดุ
และความสามารถในการขึ้นรูปของวัสดุ
Af
L
A0
L0
20
21. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Modulus of toughness
เป
็ นค่า strain energy density ที่วัสดุกักเก็บไว้ก่อนที่จะเกิดการ
แตกหัก หรือ พลังงานที่วัสดุรับได้โดยไม่แตกหัก มีความสาคัญใน
การป
้ องกันการพังทลายของโครงสร้าง โดยวัสดุที่มีค่า Ut สูงๆ มัก
มีการเสียรูปมาก ซึ่งเป
็ นสัญญาณเตือนก่อนเกิดการแตกหัก
Strain
Ductile material
Stress
Strain
Brittle material
Stress
21
22. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
สมบัติเชิงกลที่ได้จากการทดสอบแรงดึง
มอดุลัสของความยืดหยุ่น (Modulus of elasticity)
ความต้านทาน ณ จุดคราก (Yield strength)
ความต้านทานแรงดึงสูงสุด (Ultimate tensile
strength)
เปอร์เซ็นต์การยืดตัว (Percent elongation)
เปอร์เซ็นต์การลดลงของพื้นที่หน้าตัด (Percent
reduction of area)
22
23. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
ความสัมพันธ์ระหว่างความแข็งและความต้านแรงดึง
HB
45
.
3
(MPa)
UTS
=
HB
500
(psi)
UTS
=
For Steel
23
24. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
24
Residual Stress and Distortion
25. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
25
Residual Stress and Distortion
44. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
กิตติพงค์ นิมากร
นักทดลองวิทยาศาสตร์บริการ
kittiphong@tistr.or.th
October 13, 2015
ศูนย์พัฒนาและวิเคราะห์สมบัติของวัสดุ (ศพว.)
44
45. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
45
Measuring and Testing
❖Those used to measure a mechanical property –
Quantitative tests
❖Those used to assess the joint quality –
Qualitative tests
46. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
46
Residual stress measuring
❖Methods x-ray diffraction(XRD)
❖Ultrasonic methods
❖Magnetic methods(BARKHAUSEN NOISE)
❖Electronic Speckle Pattern Interferometry
❖Hole drilling and strain gage technique
❖Core Hole drilling and strain gage technique
Residual Stress and Distortion
48. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
48
Methods x-ray diffraction(XRD)
Residual Stress measuring
ASTM standard E 1426-91
49. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
49
Ultrasonic methods(UCC)
Residual Stress measuring
50. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
50
Electronic Speckle Pattern Interferometry
Residual Stress measuring
51. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
51
Residual Stress and Distortion
Magnetic methods(BARKHAUSEN NOISE)
52. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
52
Residual Stress and Distortion
Magnetic methods(BARKHAUSEN NOISE)
- The MBN technique has a somewhat limited range of stress sensitivity,
Around ±300 MPa, and a few mm depth of measurement.
- Measurement times of a few seconds and spatial resolutions
in the sub-mm range are possible with magnetic methods.
53. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
53
DIC (Digital Image Correlation)
Residual Stress measuring
54. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Stress Concentration
What?
Stress at a geometrical
discontinuity is much higher
than the stress at a nominal section
How?
Experiment, theory, FEA
57. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
57
Residual Stress and Distortion
Hole drilling and strain gage technique
58. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
58
Residual Stress and Distortion
Core Hole drilling and strain gage technique
60. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
60
Residual Stress and Distortion
61. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
การวิเคราะห์ความเค้น-ความเครียด
(Stress-Strain Analysis)
ความเครียดของวัสดุเกิดขึ้น เนื่องจากการรับภาระกรรม
ภายนอกส่งผลให้เกิดการเปลี่ยนแปลงภายในเนื้อวัสดุ เช่น
แรง ความดัน โมเมนต์ การเปลี่ยนแปลงอุณหภูมิ เป
็ นต้น
สเตรนเกจถูกประยุกต์ใช้วัดความเครียดในเนื้อวัสดุ ใน
สภาวะที่มีการใช้งานจริง และนาค่าความเครียดมาคานวณ
เพื่อวิเคราะห์ความเค้น ทาให้สามารถทานายอายุการใช้
งานชิ้นส่วนได้
61
62. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Hook’s Law
=
E
จากหลักการการเปลี่ยนรูป
ในช่วงอิลาสติก ซึ่งมีดัชนีการ
ยืด-หดตัว หรือ modulus
of elasticity คงที่ตามกฎ
ของฮุค
สเตรนเกจจึงถูกนามาประยุกต์ใช้
ในการวัดความเครียดในเนื้อวัสดุ
1
62
63. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Concepts of Strain
64. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Strain Measurement by Strain Gage
Why?
Direct strain measurement→ Indirect stress calculation
Where?
Body surface: plane stress
How?
Electrical resistance strain gage
Concepts of Strain
65. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
สเตรนเกจ (Strain Gage)
สเตรนเกจ คือ เซนเซอร์แบบความต้านทานชนิดหนึ่งที่ทา
หน้าที่เปลี่ยนปริมาณความเครียดในรูปของปริมาณเชิงกล
ให้เป
็ นปริมาณค่าทางไฟฟ
้ าในรูปของการเปลี่ยนแปลงความ
ต้านทาน
65
66. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Stress Calculation Procedures
Strain Gage/Rosette
Attachment
Wheatstone
Bridge
Strain
(a, b, c)
Strain
(x, y, xy)
a
b
c
Transformation
Measuring
Wiring
Concepts of Strain
67. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
Strain Rosette Equations
0o – 45o – 90o (Rectangular)
90
0
45
90
0
o
o
o
2
o
2
90
o
o
o
2
o
2
45
o
o
o
2
o
2
0
2
,
,
90
cos
90
sin
90
sin
90
cos
45
cos
45
sin
45
sin
45
cos
0
cos
0
sin
0
sin
0
cos
−
−
=
=
=
+
+
=
+
+
=
+
+
=
xy
y
x
xy
y
x
xy
y
x
xy
y
x
x
y
0
45
90
Concepts of Strain
68. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
หลักการทางานของสเตรนเกจ
การทางานของสเตรนเกจอาศัยหลักการพื้นฐานของการ
เปลี่ยนแปลงความต้านทานกระแสไฟฟ
้ าของชั้นโลหะแผ่น
บางเมื่อสัมผัสกับวัสดุที่มีความเครียด
ความเครียดในเนื้อวัสดุแบ่งออกเป
็ น 2 ชนิด
ความเครียดแบบดึง (tensile strain) แสดงโดย
เครื่องหมาย + หมายถึง มีการยืดตัว
ความเครียดแบบอัด (compressive strain) แสดงโดย
เครื่องหมาย - หมายถึง มีการหดสั้นลง
68
69. TISTR
Thailand Institute of Scientific and Technological Research – TISTR www.tistr.or.th
ข้อดีของการใช้สเตรนเกจเพื่อวัดข้อมูลทางกล
สามารถแยกวัดความเค้นแต่ละประเภทที่เกิดขึ้นบนชิ้นส่วนได้
มีความผิดพลาดต่า เนื่องจากสามารถชดเชยผลกระทบจากสิ่งแวดล้อม
ต่อการวัดได้ เช่น ความผิดพลาดที่เกิดจากการเปลี่ยนแปลงอุณหภูมิ
มีความละเอียดสูง สามารถวัดความเครียดในระดับไมโครเมตร
สามารถวัดได้ในช่วงอุณหภูมิถึง -196˚C to +1000˚C
ไม่มีข้อจากัดเกี่ยวกับชิ้นส่วนที่ถูกวัด เนื่องจากสเตรนเกจมีขนาด
เล็กและน้าหนักเบา
สามารถวัดได้ในสภาวะสถิตย์ (static) และสภาวะพลวัต
(dynamic)
สามารถใช้ผลิตทรานสดิวเซอร์สาหรับการวัดแรง โมเมนต์ ความ
ดัน และการขจัด เป
็ นต้น
69