Effect of micro-content tellurium on cutting performance of 38MnVS non-quenched and tempered steel
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摘要: 为探讨碲改质对非调质钢切削性能的影响机制,对38MnVS非调质钢进行了加碲的硫化物改质试验,并对比加碲对钢中硫化物形态及切削性能的影响。结果表明,加入微量碲(0.0020%)后钢中硫化物形态显著改善,硫化物长宽比降低;由于加碲后硫化物形态的改善,降低了切削过程中的切削力,减小了刀具的磨损,阻止了积屑瘤的产生,同时改善了工件表面粗糙度,从而改善非调质钢的切削性能。Abstract: In order to explore the mechanism of effect of tellurium modification on the machinability of non-quenched and tempered steel (NQTS), a sulfide modification test of 38MnVS NQTS with tellurium was carried out, and effect of tellurium modification on morphology of sulfide and machinability of steel was compared. The results show that with tellurium addition, the morphology of sulfide in steel is significantly improved, and the aspect ratio of sulfide decreases. Due to the improvement of sulfide morphology after tellurium modification, the cutting force during cutting process is reduced, therefore tool wear is reduced and the generation of chip buildup is prevented as well. Consequently, the workpiece surface roughness is improved, thus improving the cutting performance of NQTS.
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Key words:
- non-quenched and tempered steel /
- machinability /
- tellurium /
- sulfide
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表 1 38MnVS钢主要化学成分
Table 1. Main chemical compositions of 38MnVS6 steel
% 试样 C Si Mn P S Cr V Ni Ti Te AN 0.39 0.56 1.40 0.010 0.054 0.17 0.13 0.03 0.012 — AM 0.39 0.57 1.42 0.010 0.054 0.17 0.13 0.03 0.013 0.0023 表 2 非调质钢中硫化物评级情况
Table 2. Ratings for sulfide inclusion in NQTS
试样 硫化物级别 平均面积/μm2 等效直径/μm 平均长宽比 细系 粗系 AN 3.0 2.0 14.03 4.01 4.92 AM 2.5 1.5 12.89 3.61 2.91 表 3 两种材料铁素体含量及显微硬度测量结果
Table 3. Measurement results of ferrite fraction and microhardness of the two steels
试样 铁素体含量/% 硬度(HV) AN 26 268.4 AM 28 270.2 表 4 不同材料切削力的平均值
Table 4. Average value of cutting force for AN and AM steels
N 材料 Fx/N Fy/N Fz/N F合/N AN 107.1 476.8 149.4 511.0 AM 100.8 449.0 164.8 488.8 表 5 两种材料的车削刀片磨损情况
Table 5. Wear of turning inserts for AN and AM steels
材料 刀片磨损长度/mm 改善比值/% AN 3.75 - AM 1.73 53.87 -
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