Effect of quenching process parameters on distortion in simple shaped aluminum castings

摘要

The effects of process parameters on distortion in aluminum castings are reviewed. The results of statistically designed experiments conducted with simple shaped A356 castings are introduced. The effects of process and part parameters on the average distortion and standard deviation in distortion are discussed. THE RELIABILITY OF CASTINGS is affected to a great extent by residual stresses generated during quenching (1,2). Residual stresses also cause dimensional variation problems after macnining, especially in applications that require thight dimensional tolerances. The magnitude and distribution of residual stresses vary from casting to casting even if all scastings have been quenched in the same bath and in the same batch. Distortion patterns in castings after quenching varies so much that straightening has become a profession in itself (3). Since distortion during quenching is the main cause of residual stresses in aluminum parts (4), the reduction of average distortion as well as the variation in distortion is highly desirable.