熱間工具鋼の被削性におよぼすSi量の影響

概要

論文の詳細を見る
This study has been carried out to clarify the effect of Si content on machinability of 5%Cr-3%Mo type hot working die steel hardened and tempered to 49HRC. The results are as follows. (1) Carbides retained in hardened and tempered specimens are M6C and MC and the amount of these carbides decrease with the decrease in Si content. (2) In end-milling, carbide tools exhibit shorter life with decreasing Si content, especially at the range of Si content less than 0.3%. Adhesive wear increases with the decrease in Si content. (3) In turning by carbide tools, the cutting forces and temperatures rise with decreasing Si content. (4) High speed tensile test at elevated temperatures reveals that the steels with lower Si content show higher maximum flow stress and larger reduction of area. (5) By the calculation of turning-cutting forces based on the two-dimensional cutting model, it is found that the decrease in Si content raises the shear stress resulting in the increase of cutting forces. The high shear stress of lower Si steels is considered due to their high strength at elevated temperature.
電気製鋼研究会の論文