碲对303Cu易切削不锈钢切削性能的影响

Effect of tellurium on machinability of 303Cu free cutting stainless steel

为进一步提升303Cu易切削不锈钢切削性能,满足高端客户对切削性能更高的需求,开展了向303Cu易切削不锈钢中添加碲元素的工业试验,并对含碲303Cu不锈钢进行易切削相解析,借助测力仪、表面粗糙度仪等开展了量化切削对比试验。试验结果表明,碲的质量分数分别为0(不含碲)、0.0036%、0.0070%的303Cu不锈钢盘条,在切削线速度为22.14 m/min、切削深度为0.15 mm、进给量为0.20 mm/r的切削条件下,切削力分别为61.47、51.43、48.51 N,表面粗糙度Ra分别为10.61、8.86、5.91μm,“C型屑”所占比例分别为36%、53%和78%。碲的添加改善了钢中硫化物的形貌及分布,硫化物尺寸变大,长宽比降低,更接近椭球状;增加了材料的断屑性,减少了积屑瘤,进而切削力变小、表面光洁度提升,“C型屑”比例增加;随着钢中碲含量增加,切削性改善更加显著。

In order to further improve the cutting performance of 303Cu free cutting stainless steel and meet the higher cutting performance requirements of high-end customers,industrial test of adding tellurium to 303Cu free cutting stainless steel was carried out,and the free cutting phase analysis of 303Cu tellurium-containing free cutting stainless steel was carried out.Quantitative cutting contrast experiment was carried out with the help of dynamometer,surface roughness meter,etc.The experimental results show that under the condition of 22.14 m/min cutting speed,0.15 mm cutting depth,0.20 mm/r feed,the cutting forces of 303Cu stainless steel wire rods with tellurium mass fraction of 0(excluding tellurium),0.0036%and 0.0070%,respectively,are 61.47,51.43 and 48.51 N,respectively,and the surface roughness Ra is 10.61、8.86 and 5.91μm,and the proportion of C-type chips is 36%,53%and 78%respectively.The addition of tellurium improves the morphology and distribution of sulfide in steel.The sulfide size becomes larger,the length width ratio decreases,and the shape of sulfide is closer to the ellipsoidal shape.It increases the chip breaking property of the material,reduces the built-up edge,and further reduces the cutting force.Moreover,it improves the surface finish and increases the C-type chip ratio.With the increase of tellurium content,the machinability is notable improved.