What is Post Weld Heat Treatment (PWHT)?

What is it? Why is PWHT needed? How is PWHT done?

Have you heard of post weld heat treatment (PWHT)? Of course you have. If you are involved in welding you have definitely heard this term.  But what is PHWT? When is PWHT required?  What temperature should PWHT be done at?  Heat treating of materials can be a very complicated subject, but when it comes to […]

The Importance of the Heat Affected Zone (HAZ)

When we weld we generate enough heat in the welding arc to melt the filler metal and base material.  Or just the base material is we are welding autogenously (as in GTAW without filler).  The edges of the base material melt and combine with the filler metal to create what is called the composite zone.  […]

Preventing Hydrogen Induced Cracking

Our last post (Factors Influencing Hydrogen Induced Cracking) went over the factors that contribute to hydrogen-induced cracking.  We will now go over how to prevent HIC from happening.  If you recall, we mentioned you need all three factors to be present in order to have HIC:  These factors are 1. a susceptible microstructure, 2. threshold […]

Factors Influencing Hydrogen Induced Cracking

Hydrogen-induced cracking (HIC) is a far too common type of failure. It is also called hydrogen assisted cracking (HAC) and delayed cracking since it does not occur right after welding, but a few hours or days after the weld has completely cooled down to ambient temperature.  Cracking occurs due to a significant loss in ductility […]