Martensitic Transformation Temperature Ms

Physicochemical Mechanism of Action

The martensitic transformation temperature Ms is the limit below which austenite transforms to martensite. This process occurs through rapid cooling and forms glass-hard grains.

Metallurgical Relevance & Risks in Welding

Cooling too fast below the Ms temperature can lead to martensite formation, which increases hardness but reduces crack resistance. This can lead to hot cracks and distortion.

Workshop Practice & Action Instructions

To avoid martensite formation, controlled cooling should be used. For stiff alloys (e.g., HSS), slower cooling is necessary to not drop below the Ms temperature.