Manufacturing method of directly cold-drawn spring steel wire with excellent fatigue performance

A technology of fatigue performance and manufacturing method, applied in the direction of manufacturing tools, heat treatment process control, furnace type, etc., can solve the problem that there is no special requirement for high-speed wire-controlled cooling, and achieve reduced intermediate annealing process, excellent fatigue performance, and low energy consumption Effect

Active Publication Date: 2013-06-19
NANJING IRON & STEEL CO LTD
View PDF2 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Chinese patent ZL200410085340.3 reports the preparation method of spring steel 55CrSi, which is prepared by the process of electric furnace smelting, LF refining, VD degassing, continuous casting, and high-wire rolling. There is no special requirement for high-wire controlled cooling
Generally speaking, the smelting and rolling technology of spring steel 55SiCr has been studied to a certain extent, but there is still a certain gap in the production and preparation of direct cold drawn spring steel 55SiCr wire with excellent fatigue performance.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Manufacturing method of directly cold-drawn spring steel wire with excellent fatigue performance
  • Manufacturing method of directly cold-drawn spring steel wire with excellent fatigue performance
  • Manufacturing method of directly cold-drawn spring steel wire with excellent fatigue performance

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Φ5.5mm specification hot-rolled spring steel wire rod, its chemical composition, by weight percentage, contains C: 0.54%; Si: 1.46%; Mn: 0.69%; Cr: 0.69%; P: 0.007%; S: 0.008%; O: 0.001%; ​​Als: 0.005%; the balance is composed of iron and unavoidable impurities.

[0030] Its smelting and rolling process:

[0031] Converter / electric furnace smelting tap temperature ≥ 1600°C, P ≤ 0.015%, C ≥ 0.15%, adding silicomanganese and ferrosilicon for deoxidation; LF refining adding silicomanganese, ferrosilicon, high-carbon ferrochrome for alloying; VD vacuum The treatment is kept at a high vacuum of 0.5 Torr for more than 15 minutes; the initial rolling temperature is 1008°C, the pre-finishing temperature is 950°C, the finishing rolling temperature is 900°C, and the spinning temperature is 837°C; the temperature in the continuous annealing production line is 701°C, and the fast cooling section The average cooling rate is 5.2°C / s, the temperature leaving the continuous annealing ...

Embodiment 2

[0042] Φ13.0mm specification hot-rolled spring steel wire rod, its chemical composition, by weight percentage, contains C: 0.55%; Si: 1.44%; Mn: 0.70%; Cr: 0.68%; P: 0.009%; S: 0.007%; O: 0.001%; ​​Als: 0.006%; the balance is composed of iron and unavoidable impurities.

[0043] Its smelting and rolling process:

[0044] Converter / electric furnace smelting tapping temperature ≥ 1600°C, P ≤ 0.015%, C ≥ 0.15%, adding silicomanganese and ferrosilicon for deoxidation; LF refining adding silicomanganese, ferrosilicon, and high-carbon ferrochrome for alloying; VD vacuum The treatment is kept at a high vacuum of 0.5 Torr for more than 15 minutes; the initial rolling temperature is 1018°C, the pre-finishing temperature is 955°C, the finish rolling temperature is 910°C, and the spinning temperature is 846°C; the temperature in the continuous annealing production line is 710°C, and the fast cooling section The average cooling rate is 4.5°C / s, the temperature leaving the continuous anne...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
tensile strengthaaaaaaaaaa
reduction of areaaaaaaaaaaa
tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a manufacturing method of a directly cold-drawn spring steel wire with an excellent fatigue performance. In the method, the spring steel wire is obtained through heating twice for formation and a three-step controlled cooling process, and a large square continuous cast blank is obtained via an electric arc furnace (EAF), a low-frequency (LF) refining furnace and vapor density (VD) treatment and is subject to heat transfer, heating, blank opening with a 950 mill, reheating, controlled rolling and spinning. In the three-step controlled cooling process, the wire is cooledrapidly at an average cooling speed of 4-6 DEG C per second on the temperature section from spinning to arrival at a continuous annealing production line, is cooled slowly at an average cooling speedof 0.3-1.0 DEG C per second on the temperature section from the arrival at the continuous annealing production line to departure from the continuous annealing production line, and is then naturally cooled to the room temperature with air as a cooling medium after the departure from the continuous annealing production line, and thus the finished spring steel wire can be obtained. The spring steel wire not only has high plasticity, toughness and strength and excellent fatigue performance, but also has an excellent cold-drawing performance.

Description

technical field [0001] The invention belongs to the field of alloy steel and its manufacturing process, and relates to a method for manufacturing a silicon-chromium spring steel wire rod with excellent fatigue performance and excellent direct cold drawing performance. Background technique [0002] In recent years, with the rapid development of China's automobile industry, the market demand for spring steel is increasing. According to statistics, the domestic supply and demand of spring steel in 2010 will be more than 1.5 million tons. The important parts of the automobile engine, the valve spring, the suspension spring of the shock absorption system and the clutch spring, etc., all need to be directly cold-drawn on the hot-rolled spring steel wire as the raw material. Therefore, it has superplasticity, high strength, and excellent cold drawing. The hot-rolled wire rod with excellent drawing performance has a significant effect on increasing the drawing rate, reducing the num...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B21C37/04C22C38/18C21D9/52C21D1/26C21D11/00
Inventor 王德炯孙彦辉孔祥华沈朴恒李文浩刘虎
Owner NANJING IRON & STEEL CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products