Martensite Start Temperature Formula
The martensite start temperature formula calculates the temperature at which austenite transforms to martensite. It accounts for the alloying elements in the steel.
Physikalisch-chemischer Wirkmechanismus
The martensite start temperature (Ms) is the threshold temperature at which austenite transforms to martensite. This transformation is diffusionless and depends on alloying elements like carbon and other elements in the steel.
Metallurgical Relevance & Welding Risks
A too-high Ms temperature can lead to glass-hard martensite, which increases hardness but reduces toughness and formability. A too-low temperature can result in too much retained austenite and thus a fine grain, which reduces strength.
Werkstattpraxis & Handlungsanweisungen
To set the Ms temperature correctly, you need to know the steel's alloy content. Use the formula Ms = 460 + 82 * C^(1/3), where C is the carbon content in %. Make sure the cooling steps in the welding process keep the temperature within the critical temperature window.