AbstractComposition varies sufficiently widely within an alloy specification to allow significant variations in the temperature ranges within which the austenite phase transforms to martensite. It has been suggested that such variations in composition are associated with anomolous fluctuations in the distortions produced in quenched components of a particular alloy. In the present work, a plane stress infinite plate mathematical model was used to conduct a quantitative examination of the connection between these compositional variations, the associated changes in the Msand Mftemperatures, and the amount of residual stress and strain after quenching. The residual strains at the end of a water quench increased substantially as the Mstemperature increased. However, the corresponding stresses after the same water quench and both the residual stresses and strains at the end of an oil quench were only slightly affected by such changes in the Mstemperature. This displacement in the temperature range within which transformation occurred reduced the absolute value of the transformation strain, one of the components contributing to total strain. At the end of the quench the sum of the other strain components was positive and larger than the negative transformation strain, so the reduction in the absolute value of the latter, associated with the increase in the Mstemperature, led to the increase in the residual strain at the end of the quench. The results obtained support the suggestion that the limitations of fluctuations in composition within the alloy specification are beneficial to the control of distortion in quenched components, although the most desirable compositions are those that produce a lower rather than a higher Mstemperature.MST/367