70Nb合金钢丝双相区球化退火工艺

 采用正交试验法研究了大塑性变形70Nb合金钢丝双相区球化退火工艺。结果表明，在冷却速度一定(30 ℃/h)的条件下，决定球状碳化物尺寸的主要因素是保温时间(极差为0407，可信度达到67%)。最佳工艺参数为：加热温度770 ℃，加热时间60 min，保温温度680 ℃，保温时间360 min。其球状碳化物颗粒直径为181 μm，球化等级在35~40 级范围内，硬度HV 1681，较好的达到了锡林针布的使用标准。

Intercritical Annealing Process of 70Nb Alloy Steel Wire

The intercritical annealing process of 70Nb alloy steel wire with severe plastic deformation is studied by using orthogonal test method. The results indicate that with definite 30 ℃/h cooling rate, the main factor for the grain size of spheroidal carbide is holding time whose limit deviation is 0407 and confidence level is 67%. The optimized process parameters are as follows: heating temperature 770 ℃, heating time 60 min, holding temperature 680 ℃, and holding time 360 min. And the diameter of spheroidal carbide is about 181 μm and the microhardness is about HV 1623, reaching spheroidization class 35 to 4. The material meets the requirements of cylinder wire cloth.