论文部分内容阅读
烧结硬化使粉末冶金零件可在一般烧结炉的冷却带进行硬化 ,而不需要在烧结后进行热处理。为开发用于可再充电的电动工具用的高速、高扭矩齿输 ,试验了掺加有 2 0 %Cu与 0 90 %石墨的预合金化粉末ATOMET 4 70 1 (0 4 5Mn - 0 4 5Cr - 0 9Ni- 1 0Mo)。将零件生坯压制到密度 6 85 g/cm3 ,在 1 1 2 0℃下于吸热性煤气气氛中烧结 30min。烧结态零件 (密度 6 80g/cm3 )的表观硬度为 37HRC。显微组织分析表明 ,在烧结炉冷却带充分产生了马氏体相变。随后 ,零件在 1 80～ 2 1 0℃下回火 0 5～ 4h。在 1 80℃回火 2h后 ,烧结硬化材料的力学性能与齿输齿的精度处于最佳结合状态 ,优于经热处理的烧结低合金钢材
Sintering Hardening enables powder metallurgy parts to be hardened in the cooling zone of a typical sintering furnace without the need for heat treatment after sintering. To develop high-speed, high-torque gearboxes for rechargeable power tools, pre-alloyed powders ATOMET 4 70 1 (0 4 5Mn - 0 4 5Cr - 0 9Ni- 1 0Mo). The green parts were pressed to a density of 6 85 g / cm3 and sintered at 1120C for 30 minutes in an endothermic gas atmosphere. The apparent hardness of sintered parts (density 6 80g / cm3) is 37 HRC. Microstructure analysis showed that martensitic transformation was sufficiently produced in the cooling zone of the sintering furnace. Subsequently, the parts were tempered at 180 to 210 ° C for 0.5 to 4 hours. After tempering at 180 ℃ for 2h, the mechanical properties of the sintered hardened material are optimally combined with the accuracy of the tooth delivery, which is better than that of the heat treated sintered low alloy steel