THE STUDY CONDITIONS OCCURRENCE OF HOT TEARING IN THE BILLETS ALLOY EN AW6060 PRODUCED WITH THE PROCESS OF DIRECT CHILL CASTING

摘要

During Direct Chill casting of aluminum alloys technology Wagstaff AirSlip, the primary andrnsecondary cooling causes strong thermal gradients, which leads to the uneven thermalrncontraction in different sections of the billet. The consequences are manifested appearance ofrncasting defects such as hot tearing and residual stresses. In order to reduce the occurrence ofrnthese defects were studied different effects on the formation of hot tearing: changes ofrntechnological parameters, chemical composition and microstructure of the alloy EN AW 6060rnaccording to the length and cross section, and the conditions of occurrence and progression ofrncracks describes the model the ratio of light and heavy metals in the billet. Additional testing ofrnas - cast, cracked and homogenized sample billets in multiple directions cross-section detectsrnthat the rapid cooling of the surface of the billet affect the development of fields measuredrnhardness.