Study On The Process And Properties Of KSC72A Steel Wire Water Bath Quenching

At present, most of the domestic steel production by the quenching medium for liquid lead, the reason is lead liquid has good high temperature cooling capacity, larger specific heat capacity, and no change of state, can ensure the wireoccurred sorbite transformation in a near isothermal state.but lead vapor in lead bath has a greater harm to environment and human body. In order to expand steel production capacity in response to the national policy of environmental protection, it is necessary to develop a kind of environmental pollution, efficient sorbitized treatment process.Water quenching can well overcome the drawbacks of patenting, and with advantages of.economic, efficient, environmental friendly.This paper useed AQ110 as additive of steel wire water bath quenching, by the KR-SQTAⅡtype cooling curve tester to analysis cooling performance of medium, studied the cooling characteristics of different concentration and the temperature of water bath quenching medium systematically; by optical microscope, field emission scanning electron microscopy, Vickers microhardness meter, tensile test machine, non-contact2 D video measuring instrument, X-ray diffraction, DC voltage resistance tester, bending fatigue testing machine etc. equipment, studied the parameters of production line with Φ0.8mm KSC72 A steel in quenching bath effect on microstructure and properties, and the results were compared with the steel wire of the lead bath quenching.At the same time, study on organization and performance during the process of wire drawing water quenching.The results show that: water bath quenching medium and optimization parameters of process is: concentration of 10%, the temperature is 90 ℃.The temperature effects on vapor quenching medium was significantly higher than that of the increase of the concentration of stability.Under laboratory conditions, different diameter of steel wire in the quenching medium in continuous cooling after the treatment, organize all martensite;in quenching medium after annealing, Φ3.4mm above steel wire structure is sorbite.The optimal parameters of test production line with Φ0.8mm KSC72 A were: austenitizing furnace five temperature was 990℃,1000℃,1025℃, 1010℃ and 980℃ water bath length 20 cm, linear velocity68m/min.Under this parameter the microstructure and properties of the steel wire are comparable to the lead bath quenching steel wire,the bending fatigue performance of water bath quenching steel wire drawing to finished wire is slightly better than that of the steel wire quenched in lead bath, so water quenching can replace the lead quenching.Water bath quenching steel wire in drawing process, with increasing strain, cable’s team began to deformation along the drawing direction,eventually become fibrous tissue.Different orientations of the cable martensite layer corresponding to different deformation and refinement, the cable’s body layers and ultimately to the direction parallel to the drawing direction, under great strain, part of the cable’s body layer rupture.In the wire drawing process, with the increasing of strain, the diffraction peaks were shifted to the left, the lattice constant increases, crystal distortion increased.In addition, the diffraction peak intensity ratio can reach the {110}planes ultimately turned to the drawing direction, parallel to the drawing direction.