Production method of steel for automobile flywheel gear ring

Abstract

The invention relates to a production method of steel for an automobile flywheel gear ring. The production method comprises the following process steps: (1) smelting: controlling the alkalinity of an LF (ladle furnace) to be 6.0-8.0, vacuumizing to be below 67 Pa in a VD (vacuum degassing), keeping the vacuum for 15 minutes, softly blowing for 20 minutes, casting on a platform, and controlling the outbound temperature to be 45-50 DEG C higher than the liquidus temperature; (2) continuous casting: the specific water flow is 0.98 L / kg, the superheat degree target value of a tundish is 30-35 DEG C, and the temperature of the central point of the inner cambered surface of a casting blank entering a withdrawal and straightening machine is monitored to be 1100-1150 DEG C; (3) rolling: rolling is controlled, the heating time of the casting blank is 80-100 minutes, the temperature of a high-temperature section is controlled to be 1120-1170 DEG C, the time is 60-80 minutes, and the tapping temperature is controlled to be 1010-1070 DEG C; (4) controlled cooling: after rolling, direct water cooling and slow cooling are performed, the curling temperature is controlled to be 755-785 DEG C, and the cooling rate is 3-5 DEG C / s; and (5) slow cooling is conducted, specifically, the coiled wire rod enters a slow cooling area surrounded by asbestos to be slowly cooled, the temperature is slowly cooled to 500-540 DEG C from 700-760 DEG C, a tough structure with pearlite and ferrite as a matrix is obtained, and the structure and the mechanical property of the wire rod are uniform.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and relates to a production method of steel for automobile flywheel ring gear. Background technique [0002] With the rapid development of the automotive industry, the market demand for automotive steel is increasing. In the production of wire rods with ferrite and pearlite as the main structural characteristics, due to the unreasonable control of curling temperature, hood temperature, and cooling rate, it is easy to produce coarse and uneven grains, and the pearliteization is low, which will lead to processing. and deterioration of wire rod performance. In this way, the structure and mechanical properties of the wire rod are not uniform, resulting in problems such as processing cracking and low processing rate, which brings great inconvenience to the processing and use of downstream customers. [0003] At present, the research on carbon steel in the existing technology mainly focuses on the...

AI Technical Summary

Problems solved by technology

In the production of wire rods with ferrite and pearlite as the main structure characteristics, due to unreasonable control of coiling temperature, hood temperature, and cooling rate, etc., it is easy to cause coarse and uneven grains, and low pearlitization, which will lead to processing and deterioration of wire rod performance

In this way, the structure and mechanical properties of the wire rod are uneven, resulting in problems such as cracking and low processing rate, which brings great inconvenience to the processing and use of downstream customers.

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