This document discusses the weldability of carbon and alloy steels. It states that weldability is affected by various parameters related to the steels, including the process used, the purpose of the welding, and fabrication conditions. It lists some key parameters that influence weldability, such as oxidation tendency, chemical composition, mechanical properties, and physical properties. The document also notes that carbon steels are an alloy of iron and carbon, with carbon occupying interstitial spaces in the alloy. It indicates that high carbon steels typically contain 0.5-0.8% carbon.

1. Dr. Shailesh Kumar Dewangan
Assistant Professor
Department of Mechanical Engineering
CEC Bilaspur
Advance Welding Technology
Weldability of Carbon and Alloy Steels

2. • weldability of the carbon steel and alloy steel is affected by the various
parameters related with these steels
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Weldability of Carbon and Alloy Steels
• Easy of welding by a Process for a given purpose under set of given
fabrication condition
Easy of welding

3. • Weldability is process, purpose and fabrication condition
• Process - Different process (GMAW, GTAW, SMAW, SAW, PAW …)
• Procedure – Preheat, Edge preparation, cleaning of surface, process parameters,
post heat treatment
• Purpose – Temperature, load, environmental
• Fabrication condition - Different thickness of weld metal
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Influence of Parameters on Weldability
Metal A Metal A

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Weldability of Metal
• oxidation tendency
• evaporates
• affinity with the atmospheric gases
• structure of the metal
• chemical composition
• Yield strength
• Elongation indicating the ductility
• Toughness
Chemical Properties
Mechanical Properties
• Thermal conductivity (k)
• Expansion coefficient
• Solidification, temperature range (STR)
• solidification temperature range
Physical Properties

5. • Weldability of steels we know that these are alloy of iron plus carbon
Fe + C
• Carbon mostly occupies the interstitial space in such kind of alloys
and in simple carbon steels mostly we have the carbon in very
controlled conditions thereafter magnesium, silicon, sulphur and
phosphorus
• Mostly the high carbon steels are found out to say 0.5 to 0.8 so this is
the range for the different kind of carbon residue
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Weldability of Steel

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