Effect of Rare Earth Elements on Thermal Fatigue of High Ni－Cr Alloy Cast Iron

The effect of RE on crack forming and developing of hot rolled high Ni-Cr alloy cast iron during thermal fatigue test was investigated.It shows that the serviceable life of hot rolled high Ni-Cr alloy cast iron can be improved by RE.The number of cycle before fracture was increased by 42%～163%.The optimum of RE addition is 0.05 wt%～0.15wt%.

连轧钢管机凹型槽轧辊的研制

本文选用镍铬钼合金球墨铸铁材质 ,凹型槽直接铸出工艺 ,试制连轧钢管机轧辊。在冲天炉熔炼条件下 ,炉前采用轻稀土镁复合球化、孕育处理工艺 ,球化等级达到了 2～ 3级。各项性能指标达到了GB/T15 0 4- 91的要求 ,轧辊使用性能达到了国内知名厂家同类产品的先进水平。