回火工艺对织针弹性及硬度的影响

Effect of tempering process on elasticity and hardness of knitting needles

就回火工艺对织针弹性及硬度的影响进行了研究。结果表明:回火温度对织针硬度影响明显,随回火温度升高,织针的表面硬度明显降低;在同一回火温度下,回火保温时间大于60 min时,织针硬度变化不大;织针弹性主要受回火时间影响,在回火时间小于60 min时,残余变形量随温度的变化减小比较大,而当回火温度高于220℃,保温时间大于60 min时,弹性变化不大,并保持较小的残余变形量;采用适当的回火工艺,织针不仅可以具有良好的弹性,还可以有高的硬度(HV650以上)。

Abstracttempering time on the elasticity and hardness of knitting needles were studied. The results showed that tempering temperature has an obvious effect on surface hardness of knitting needles. The surface hardness lowers significantly along with tempering temperature rise. When the tempering time is over 60 minutes, surface hardness varies little at the same testing tempering temperature. And the elasticity of knitting needles is mainly influenced by tempering time. When tempering time is less than 60 minutes, the residual deformation value decreases greatly along with temperature rising. At the same time, the residual deformation value changes little and maintains a small value when tempering temperature is higher than 220 ℃ and tempering time is over 60 minutes. The needles can be rendered not only good elasticity, but also high hardness （HV650 above）by an appropriate and plentiful low-temperature tempering process.