CN102719650B - Heat treatment process for high-carbon steel wires for wire ropes - Google Patents

Abstract

The invention discloses a high-carbon carbon steel wire heat treatment process for steel wire ropes. In the process, the high-carbon carbon steel wire with a diameter of 2 mm to 5 mm is heated to a temperature of 780 ° C to 900 ° C through induction heating, resistance furnace heating or electric contact heating. ℃, and keep the heated steel wire at a temperature of 780℃～900℃ for 10 seconds to 2 minutes, then quickly put it into the salt bath and keep it in a salt bath lower than the sorbitization temperature for 1 second～ After 20 seconds, put the steel wire into a salt bath or lead bath in the range of sorbitizing temperature and hold it for 20 seconds to 1 minute, then take it out and cool it naturally, so that the sorbite of the high carbon carbon steel wire can be completed. Chemicalized heat treatment process. The invention can effectively refine the size of the sorbite group and the interlayer spacing of the steel wire and improve the uniformity of the interlayer spacing. The product has the advantages of high strength and plasticity, excellent fatigue resistance, long service life and the like. The invention has remarkable effects on improving the strong plasticity and fatigue life of the steel wire.

Description

Heat treatment process of high carbon carbon steel wire for steel wire rope

technical field

The invention relates to a high-carbon carbon steel wire heat treatment process for steel wire ropes, and belongs to the technical field of heat treatment of steel wire rope metal wires.

Background technique

In the current steel wire rope manufacturing process, it is first necessary to manufacture steel wires, then twist them into strands, and finally synthesize them into steel wire ropes. At present, the steel wires used to manufacture steel wire ropes are mainly high-carbon carbon steel wires. When producing these existing high-carbon carbon steel wires, the intermediate heat treatment process is mainly to use resistance furnace or electric contact heating, and then enter the lead bath for isothermal quenching to complete the sorbite. Because these processes are directly isothermal in the sorbite region, the interlayer spacing will not be less than 100nm, and the cluster size is between 3 and 10mm, and the performance potential of the sorbite structure cannot be fully utilized, so that the existing high-carbon The strong plasticity and strain fatigue life of carbon steel wire are not ideal. So the effect of the existing heat treatment process for steel wire rope with high carbon carbon steel wire is still not ideal enough.

Contents of the invention

The object of the present invention is to provide a high-carbon carbon steel wire heat treatment process for steel wire ropes with uniform layer spacing, small layer spacing, good strength and plasticity, excellent fatigue resistance and long service life of sorbite structure, so as to overcome the disadvantages of the prior art. insufficient.

The present invention is realized in the following way: the heat treatment process of a high-carbon carbon steel wire for a steel wire rope of the present invention is to heat the high-carbon carbon steel wire with a diameter of 2 mm to 5 mm to the temperature by means of induction heating, resistance furnace heating or electric contact heating. temperature of 780°C to 900°C, and keep the heated steel wire at a temperature of 780°C to 900°C for 10 seconds to 2 minutes, so as to achieve rapid austenitization, and then quickly put the heated steel wire into the salt Keep the steel wire in a salt bath lower than the sorbitizing temperature for 1 second to 20 seconds in the tank, and then put the steel wire in a salt bath or lead bath in the sorbitizing temperature range for 20 seconds to 1 minute. Take it out and cool it naturally, so that the heat treatment process of sorbitizing the high-carbon carbon steel wire can be completed.

When the heated steel wire is kept at a temperature of 780° C. to 900° C. for 10 seconds to 2 minutes, the steel wire with a larger diameter is held longer than the steel wire with a smaller diameter.

The temperature lower than the sorbitization mentioned above is 300°C-480°C.

The aforementioned sorbitizing temperature ranges from 500°C to 600°C.

Due to the adoption of the above-mentioned technical scheme, the present invention adopts the large supercooling and then isothermal method from the perspective of the driving force of the pearlite phase transformation, which can significantly refine the size of the sorbite organization group and the interlayer spacing, thereby improving the quality of the high-carbon carbon steel wire. It provides a new way to significantly increase the fatigue life of steel ropes. According to the diameter of the steel wire, the present invention firstly heats the steel wire to the austenitizing temperature, then quickly puts the steel wire into a salt bath lower than 480°C for a few seconds to obtain a large degree of supercooling, and then puts it into a lead bath above 500°C to complete the cable isothermally. bodying. Large undercooling can significantly increase the nucleation rate of sorbite clusters, and the isothermal temperature above 500°C makes the sorbite cluster nuclei grow rapidly to complete sorbite, and more than 93% of the sorbite structure can be obtained, and finally the steel wire is completed. heat treatment. After testing, the sorbite structure of the steel wire treated by the invention has a uniform layer spacing, and the layer spacing is generally 20-70nm, and the cluster size is less than 2mm. This plays an important role in improving the plasticity and toughness of the wire due to the significantly reduced cluster size, while reducing the interlayer spacing increases the strength level. Therefore, compared with the prior art, the present invention can effectively reduce the size of sorbite clusters and interlayer spacing, improve the uniformity of interlayer spacing, and its products have the advantages of high strength and plasticity, excellent fatigue resistance, and long service life. . The invention has remarkable effects on improving the strong plasticity and fatigue life of the steel wire.

Detailed ways

Below in conjunction with embodiment the present invention is described in further detail.

Embodiments of the present invention: when implementing the high-carbon carbon steel wire heat treatment process for a steel wire rope of the present invention, the high-carbon carbon steel wire used is the high-carbon carbon steel wire commonly used to make steel wire ropes in the prior art. , heating the high-carbon carbon steel wire with a diameter of 2 mm to 5 mm in the prior art to a temperature of 780 ° C to 900 ° C through traditional induction heating, resistance furnace heating or electric contact heating, and making the heated steel wire at 780 ° C Keep it at ~900℃ for 10 seconds to 2 minutes (the steel wire with a large diameter should be kept longer than the steel wire with a small diameter), so that it can achieve rapid austenitization, and then put the heated steel wire quickly Enter the salt tank and keep it in a salt bath at a temperature of 300°C to 480°C for 1 second to 20 seconds, then put the steel wire in a salt bath or a lead bath with a temperature range of 500°C to 600°C and keep it at an isothermal temperature for 20 seconds to 1 After 10 minutes, take it out and let it cool naturally, so that the heat treatment process of sorbite for the high-carbon carbon steel wire can be completed, and the high Carbon steel wire products.

Claims (4)

1. high-carbon carbon steel wire thermal treatment process for a wireline, it is characterized in that: by diameter, be that 2mm～5mm high-carbon carbon steel wire passes through induction heating, it is 780 ℃～900 ℃ that the mode of resistance furnace heating or Electricity Contact Heating is heated to temperature, and heated steel wire is kept 10 seconds～2 minutes at the temperature of 780 ℃～900 ℃, thereby achieve quick austenitizing, then the steel wire after this heating being put fast in salt bath into to isothermal in the salt bath lower than the sorbitizing temperature keeps after 1 second～20 seconds, salt bath or the lead bath isothermal of this steel wire being put into to the sorbitizing temperature range keep taking out naturally cooling after 20 seconds～2 minutes again, can complete the thermal treatment process to the sorbitizing of this high-carbon carbon steel wire like this.

2. high-carbon carbon steel wire thermal treatment process for wireline according to claim 1, it is characterized in that: when heated steel wire is kept to 10 seconds～2 minutes at the temperature of 780 ℃～900 ℃, the time that the steel wire that its diameter is large keeps is greater than the steel wire that diameter is little.

3. high-carbon carbon steel wire thermal treatment process for wireline according to claim 1, it is characterized in that: described is 300 ℃～480 ℃ lower than the sorbitizing temperature.

4. high-carbon carbon steel wire thermal treatment process for wireline according to claim 1, it is characterized in that: described sorbitizing temperature range is 500 ℃～600 ℃.