STUDY OF THE EFFECT OF PARAMETERS OF SCREW ROLLING ON SURFACE QUALITY OF BARS FABRICATED FROM REFRACTORY ALLOY BILLETS

摘要

New technological process of metal forming of refractory alloy billets via screw rolling is developed. The results of experimental investigations directed to the development of rational conditions for screw rolling of refractory alloy billets are presented. These conditions will provide required surface quality of fabricated bars. It is shown, that elongation ratio per pass can be considered as the most important parameter, having the effect on surface quality state of rolled material. It is recommended to implement screw rolling of billets during two passes: with 1,6-2,1 elongation ratio in the 1-st pass (for rounding of square cross section of a billet) and with its enlargement up to 1,8-2,4 in the 2-nd pass.