Process method for increasing surface quality and drawing property of ultra-fine high-carbon steel wire

Abstract

The present invention relates to a process method for increasing surface quality and drawing property of an ultra-fine high-carbon steel wire. The process method comprises: carrying out rough drawing, lead bath isothermal quenching I and medium wire drawing deformation on a high-carbon steel wire rod to obtain a steel wire with a diameter of 0.7-0.95 mm, carrying out lead bath isothermal quenching II, carrying out a surface cleaning area cleaning treatment for a certain time, carrying out air cooling, adding to a brass electroplating tank, and carrying out wet drawing deformation to obtain the ultra-high strength steel wire with a diameter of 0.10-0.12 mm. According to the present invention, the process method is adopted to eliminate the lead adhered on the lead surface so as to provide the lead scraping effect; the time of conversion of austenite into perlite is prolonged, and the cooling rate is reduced, such that the conversion of the austenite is complete; the steel wire surface oxidation is eliminated so as to provide the reduction protection effect; and proeutectoid ferrite, secondary mesh cementite and other untypical untypical structures in the ultra-fine high-carbon steel wire are less, the distance between the perlite lamellas is about 70-80 nm, and the surface does not produce decarburization phenomenon.

Description

technical field [0001] The invention relates to a process for improving the surface quality and drawing performance of ultra-fine high-carbon steel wire, so as to improve the quality of the copper coating layer of the steel wire and reduce the broken wire rate in wet drawing, especially involving diameter Φ0.70~0.95mm, carbon A process method for improving the surface quality, strength, and area reduction rate of ultra-fine high-carbon steel wire with an amount of 0.7~0.95% before brass plating and wet drawing. Background technique [0002] With the improvement of light weight and toughness requirements for products such as steel cord, cutting wire, metal card clothing and piano wire, steel wire is gradually developing in the direction of ultra-fine and high carbonization. At present, in the production process of ultra-fine high-carbon steel wire, the technological process adopted is: hot-rolled wire rod (Φ5.5mm)→rough drawing (Φ2.4~3.2mm)→lead bath isothermal quenchingⅠ→med...

AI Technical Summary

Problems solved by technology

However, there are more proeutectoid ferrite and reticular secondary cementite in the microstructure of the steel wire after the lead bath isothermal treatment II of the above process, and the pearlite lamellar spacing is thick, which reduces the work hardening rate of the steel wire , in the subsequent cold drawing deformation process, the deformation resistance is relatively large, and the cold drawing deformation of the steel wire is difficult, resulting in a high rate of wire breakage in wet drawing

At the same time, the strength and toughness of the steel wire after the lead bath isothermal treatment II of the above-mentioned process fluctuate widely, such as the strength difference of different parts of the brass-plated steel wire prepared by the same wire rod exceeds 100MPa, and the fluctuation range of the area shrinkage is ± 20%, affecting the overall consistency of steel wire performance

In addition, the surface of the steel wire after the lead bath isothermal treatment II also has obvious decarburization phenomenon, and the surface of the steel wire is easy to hang lead during the lead bath isothermal treatment. Adhesion to steel wire

These problems have seriously affected the quality of brass plating on the steel wire surface in the next step and the further wet drawing deformation performance of the steel wire