The document discusses heat treatment processes and phase transformations in nickel-titanium (NiTi) alloys. It describes the austenite, martensite, and R-phase crystal structures that NiTi can form. Heat treatments like aging, annealing, and recrystallization can be used to control the transformation temperatures and properties. The superelasticity and shape memory effects of NiTi alloys originate from stress-induced and thermal transformations between these phases. Specific NiTi alloy variants like twisted files (TF), controlled memory (CM) wire, and M-wire are discussed in terms of their manufacturing processes and resultant mechanical behaviors.
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Quenching is a vital part of the heat treating process in manufacturing. This presentation by Houghton International will show you how to master the process for the most efficient quenching and heat treating operations.
Heat treatment 1 By
P.SENTHAMARAI KANNAN,
ASSISTANT PROFESSOR ,
DEPARTMENT OF MECHANICAL ENGINEERING,
KAMARAJ COLLEGE OF ENGINEERING AND TECHNOLOGY,
VIRUDHUNAGAR, TAMILNADU.
INDIA.
FellowBuddy.com is an innovative platform that brings students together to share notes, exam papers, study guides, project reports and presentation for upcoming exams.
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# Students can catch up on notes they missed because of an absence.
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# Students can earn better grades, save time and study effectively
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Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Quenching is a vital part of the heat treating process in manufacturing. This presentation by Houghton International will show you how to master the process for the most efficient quenching and heat treating operations.
Heat treatment 1 By
P.SENTHAMARAI KANNAN,
ASSISTANT PROFESSOR ,
DEPARTMENT OF MECHANICAL ENGINEERING,
KAMARAJ COLLEGE OF ENGINEERING AND TECHNOLOGY,
VIRUDHUNAGAR, TAMILNADU.
INDIA.
FellowBuddy.com is an innovative platform that brings students together to share notes, exam papers, study guides, project reports and presentation for upcoming exams.
We connect Students who have an understanding of course material with Students who need help.
Benefits:-
# Students can catch up on notes they missed because of an absence.
# Underachievers can find peer developed notes that break down lecture and study material in a way that they can understand
# Students can earn better grades, save time and study effectively
Our Vision & Mission – Simplifying Students Life
Our Belief – “The great breakthrough in your life comes when you realize it, that you can learn anything you need to learn; to accomplish any goal that you have set for yourself. This means there are no limits on what you can be, have or do.”
Like Us - https://www.facebook.com/FellowBuddycom
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
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3. .
. Ts
.
.
. Tf
.
Stable Austenite (L)
Unstable Austenite
T
Log t
Annealing
T E (melting temp)
start
finish
Pearlite
(Fe3C)
Quenching
M s
M f
Martensite
A + P
A + M
Time Temperature Transformation (TTT)
start
finish
Atomic
mobility
decrease
Transformation
driving force
increase
Because no atomic migration is necessary, the transformations
usually progress in a time-independent fashion,
with the speed of the interface between the two phases able to
move at nearly the speed of sound.
This type of transformation is referred to as an Athermal
transformation since it cannot progress at a constant temperature,
but rather the amount of the new phase present depends only upon
temperature, not time
15. Super elasticity, or Pseudo elasticity, can be defined as the ability of certain materials to recover their original shape
after the load is removed even when they are deformed beyond their yield strength.
The driving force for the reverse-transformation is the difference
between the chemical free energy of the parent and martensitic
phases above As, and the complete shape recovery lies in that the
original orientation of the parent phase can be restored
(crystallographic reversibility).
In most metals, when an external force exceeds a given amount
mechanical slip is induced within the lattice causing permanent
deformation; however, with NiTi alloys a stress-induced martensitic
transformation occurs, rather than slip.
This effect is called Stress‐Induced Martensite (SIM) transformation.
16. Super elasticity When the stress stops without permanent deformation
occurring returning to the previous shape with a return to the
austenite phase, provided the temperature is within a specific
range austenite is transformed to martensite by stress;
for a practical example, an insertion of the instrument into a
curved root canal.
Because the stress‐induced martensitic state is not stable at the
intraoral temperature, unloading of the endodontic instrument
(e.g., withdrawal of an instrument out of a curved root canal)
leads to reverse transformation back to the austenite phase
resulting in a spring‐back of the endodontic instrument to its
original shape
17.
18. Shape memory effect
Shape-Memory Effect (SME), which is the ability of the alloy to completely recover its original shape when heated
above the martensite-to-austenite transformation temperature
The transformation induced in the alloy occurs by a
shear type of process to a phase called the martensitic
or daughter phase ,which gives rise to twinned
martensite
The deformation can be reversed by heating the alloy
above the As with the result that the properties of the
NiTi alloy revert back to their previous higher temperature
values
19. Martensite’s crystal structure has the unique ability to undergo
limited deformation in some ways without breaking atomic
bonds, known as the twinning, which consists of the
rearrangement of atomic planes without causing slip or
permanent deformation allowing to undergo about 6–8% strain
in this manner.
When martensite is reverted to austenite by heating, the
original austenitic structure is restored, regardless of whether
the martensite phase was deformed; hence, the name “shape
memory” refers to the fact that the shape of the high-
temperature austenite phase is “remembered,” even though the
alloy is severely deformed at a lower temperature.
20. Different phases of shape memory alloy at different
temperature and their relationship with loading and unloading
Superelasticity = mechanical
(Stress Induced Martensite)
Shape memory = thermal +
mechanical stress
(Thermal Induced Martensite)
21. The differences between NiTi alloys are their nickel content and their temperature
ranges of MT.
22.
23. The "premartensitic transition" precedes the martensitic transformation under certain conditions.
R-phase possesses a lower shear modulus than martensite and austenite, and the transformation
strain for R-phase is less than one-tenth that of martensitic transformation.
The two step transformations of :
(B2 Austenite → R-phase) -- and subsequent --- (R-phase → B19′ Martensite) ,, occurs upon cooling when :
Rs (the start temperature of As → R-phase transition) is below Ms (start temperature of martensite transformation)
A variety of possible Martensite variants are obtained by using
different twinned R-phase as matrix and by changing
the rhombohedral angle.
24. The R-phase transition usually appears prior to the martensitic transformation when Ms is more lowered by some means.
There are many factors effective to depress the Ms point as follows:
(1) Increasing Ni-content.
(2) Aging after solution-treatment
(3) Annealing at a low temperature immediately after cold work.
(4) Thermal cycling.
(5) Substitution of a third element
26. Ti
Ni
BCC
Body centered cubic
The crystal structures of Ni-Ti
Left: Austenite, which is ordered Face-centered cubic;
Middle: R-phase, which is rhomboidal
Right: Martensite, which is Body-centered cubic
27. Transformation temperatures are highly dependent on the nickel concentration of the
alloy.
On the Ni-rich side, increasing nickel content results in a drastic decrease in transformation
temperature.
On the Ni-rich side, Ti3Ni4 precipitates can be formed from TiNi3 decomposition.
These precipitates (TiNi3) can affect the characteristics of martensitic transformation and act as
nucleation
centers for formation of the R phase
For NiTi alloys in which SME(shape memory effect) is desired, the Ni content limits
range from 48% to 52% Ni by weight
28. The heat treatments performed in NiTi alloys with the aim of improving their
properties are:
Aging :process consists of uniform heating of the alloy to about 500°C followed by rapid cooling (quenching), usuall
in water, to temporarily prevent precipitation of the alloying elements. the aging time is an important factor affecting
the Ms temperature and consequently affecting the transformation sequence of Ti49Ni51 which is aged at 400°C, × 1 h.
Annealing :Is when The material is heated to 300–500°C until the desired changes have taken place over the
entire mass of the part, which is then cooled slowly.
Recrystallization :is the replacement of a cold-deformed structure by a new set of deformation-free grains, as eviden
reduction in hardness and an increase in ductility.
To eliminate the hardening effect caused by cold forming, annealing is performed to achieve recrystallization.
31. In the case of TF, maintaining the NiTi alloy in R-phase by heat treatment enables the twisting process.
Thus, it is easier to apply plastic deformation to R-phase because lower stress would be required.
According to the manufacturer, TF instruments are developed by:
1- Transforming a raw NiTi wire in the austenite to R-phase through a thermal process.
2- In the R-phase, the NiTi blank is twisted along with repeated heat treatment, and after additional thermal
procedures to maintain its new shape.
3- The instrument is converted back to austenite, which is super-elastic once stressed.
Attempts to twist instruments in the conventional way would probably result in instrument fracture.
R-phase possesses lower shear modulus than martensite and austenite, and the transformation strain for
R-phase transformation is less than one-tenth that of martensitic transformation.
32. The manufacturer claims that this proprietary twisting process with concurrent heat treatment and protection of the
crystalline structure imparts superior flexibility and resistance to fatigue.
TF instruments are significantly more resistant to cyclic fatigue than ground ones.
The twisting process avoids machining defects
The higher Ms temperature of TF may require the lower critical stress to induce martensitic transformation
34. CM NiTi files do not present the rebound effect after unloading, and their original shape is restored only
after autoclaving.
The behavior of these files may be explained by the presence of stable martensite, meaning that the working
temperature is below the Af.
Stable martensite is known for exhibiting the shape memory effect, which is the capacity to recover the original
shape by reverse transformation after heating the deformed martensite to temperatures above the Af
These temperatures are strictly related to the nickel content of the alloy and/or its thermomechanical
history, which is unknown for the CM NiTi wires.
The G-wire was developed in 2015, which is manufactured through several processes;
(1) by producing a mixed phase of austenitic phase, R-phase, and martensitic phase by M-wire treatment,
(2) by precipitating Ti3Ni4 in the austenitic phase,
(3) By controlling excessive growth of martensitic phase to promote the formation of R-phase
HyFlex (HF) is produced using CM wire to possess martensitic property at room temperature,
resulting in no spring back and excellent root canal trackability.
35. CM wire was a kind of Ni-rich NiTi alloy that possessed a relatively high As and Af compared with regular SE wire.
At room temperature the instrument may be a composite of R-phase martensite and austenite, unlike
conventional NiTi instruments, which are purely austenitic.
CM instruments have >300% greater resistance to cyclic fatigue when compared to SE
instruments
The transformation temperatures increase as the nickel content decreases.
Thus, with the decrease of the nickel content in the NiTi alloy, the Af increases as well as the tendency to
obtain stable martensite at the working temperature.
Furthermore, Zinelis et al showed that Hyflex CM files have a lower percentage of nickel (52.1 %wt) than do
conventional NiTi files.
37. The austenite-finish temperature of M-Wire (45°C – 50°C) is much higher than that for
conventional superelastic wire (approximately 20°C or lower)
At room temperature GTP®Series X™ instruments made from M-Wire exist in the martensite phase.
This martensite phase results from extensive thermomechanical processing that occurs during the
manufacture of the starting M-Wire segments.
The special martensite structure accounts for the superior mechanical properties of M-Wire instruments.
M-Wire instruments are largely a mixture of martensite and R-phase at room temperature, with a
small amount of austenite.
EDS analysis indicate that the approximate composition of the precipitates in the M-Wire microstructure
is TiB2BNi, which indicates that the starting wire segments are Ti-rich rather than Ni-rich.
38. M-Wire instruments have significantly higher hardness compared with conventional rotary NiTi instruments
The increased hardness of the M-Wire instruments is attributed to the special work-hardened martensite
structure found by STEM examination of starting wire blanks and metallographic examination of the etched
microstructures of instruments.
M-Wire has relatively coarse grains, numerous triple-point junctions of grain boundaries, and localized
deformation bands with microtwins, indicative of extensive thermomechanical processing.