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钢件淬火会导致其产生复杂且难以预测的尺寸和形状改变（畸变）。甚至用同一块坯料不同部位的材料制作的零件，其淬火过程中发生的畸变行为也大不相同。这是由于若干引起畸变的潜在因素（如合金元素、偏析、残余应力和相组成等）不均匀分布所造成的，而这些潜在因素作用的累积贯穿于零件制造的全过程。本文研究了合金元素的分布和偏析对淬火畸变的影响。研究用试棒为用直径45 mm的SAE 52100钢棒料加工成的不同直径圆柱体，并将其编号，以便分辨其在原棒料上的确切位置。然后将试棒装入通氮气保护的井式炉加热奥氏体化，随后进行喷气淬火。测量结果表明，试棒在淬火过程中的尺寸变化与其在坯料中的取样位置密切相关，而试棒的弯曲程度和方向与取样位置和直径之间没有显著的关联。“,”Quenching of steel components results in complex and hard-to-predict dimensional and shapechanges (distortion).Even the components manufactured from different parts of the same semifinished product may show significantly different distortion behaviours during quenching.The reason is thought to be non-uniform distribution of distortion potential carriers in the final component (i.e.alloying elements,segregations,residual stresses and phases)which are accumulated throughout the whole manufacturing chain.This study focuses on the effects of alloying element distribution and segregation on quench distortion.For this aim,long cylinders of various diameters were machined from 45 mm diameter SAE 52100 steel bars,and marked to define their exact positions in the initial bar.Then the cylinders were austenitised in a vertical furnace under nitrogen atmosphere and quenched in a gas nozzle field.The coordinate measurement results show that dimensional changes deviate significantly with machining position;however,the bending magnitudes and directions do not exhibit a distinct correlation with machining position and the cylinder diameter.