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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 steel can result in complex and unpredictable changes in size and shape (distortion). Even parts made of materials from different parts of the same blank differ greatly in their distortion behavior during quenching. This is due to the uneven distribution of a number of potential causes of distortion such as alloying elements, segregation, residual stress and phase composition, and the cumulative effect of these potential factors throughout the manufacture of parts. This article studies the effect of alloying element distribution and segregation on quench distortion. The test bars are cylinders of different diameters machined from SAE 52100 bar stock with a diameter of 45 mm and are numbered to distinguish their exact position on the original stock. The test bar was then heated austenitized in a nitrogen-protected pit furnace followed by jet quenching. The measurement results show that the dimensional change of the test rod during quenching is closely related to its sampling position in the blank. There is no significant correlation between the bending degree and direction of the test rod and the sampling position and diameter.