Subscribe to our newsletter to receive the latest news and events from TWI:

Subscribe >
Skip to content

Innovation Timeline

Heat affected zone cracking

The business was the first to identify the main factors controlling hydrogen induced heat affected zone cracking. It developed cracking tests and hydrogen measurement methods and later produced a comprehensive prediction procedure for avoiding cracking in structural steels, and determining the importance of sulphur content in cracking.

Industrial impacts

The prediction procedure formed the basis of a key British Standard for many years and now incorporates the European standard which superseded it. TWI's hydrogen measurement methods were adopted by the International Institute of Welding in the late eighties.

Spot and projection welding

The first code of practice for spot and projection welding was developed half way through the last century on the site near Cambridge where TWI is now established.

Industrial impact

These practices were immediately adopted by the International Institute of Welding and today form the basis of robotic spot welding of automotive parts.