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CN-121718824-B - Surface heat treatment process for improving strength of mining metal top beam

CN121718824BCN 121718824 BCN121718824 BCN 121718824BCN-121718824-B

Abstract

The invention discloses a surface heat treatment process for improving the strength of a mining metal top beam, which relates to the technical field of surface heat treatment and comprises the following steps of preparation of a multi-element co-cementation agent, surface pretreatment of a base material, boxing and sealing, gradient high-temperature chemical co-cementation, cooling and quenching integrated treatment, low-temperature tempering stress relief, post treatment and detection. According to the invention, through multi-element co-permeation and gradient heat treatment, a compact functional layer is constructed on the surface of the top beam in situ, so that the balance between high surface hardness and high core toughness is realized, and the service life of the top beam in the underground heavy load, abrasion and acid corrosion environments is prolonged.

Inventors

  • YE WEISONG
  • BAO HONGQIANG
  • ZHANG HUAN

Assignees

  • 山西广凯机械科技有限公司

Dates

Publication Date
20260508
Application Date
20260227

Claims (4)

  1. 1. The surface heat treatment process for improving the strength of the mining metal top beam is characterized by comprising the following steps of: S1, preparing a multi-element co-permeation agent, namely weighing 40-60% of boron carbide powder, 3-8% of rare earth magnesium silicon iron alloy powder, 5-10% of chromium powder, 1-3% of ferrous sulfide powder, 3-5% of potassium fluoborate and the balance of aluminum oxide powder or silicon carbide powder as filler according to mass percent, placing the components into a ball mill for mechanical ball milling and dispersing treatment, controlling the ball milling time to be 2-4 hours, uniformly mixing and refining particles, and screening to obtain the multi-element co-permeation agent; s2, surface pretreatment of a base material, namely performing sand blasting rust removal and ultrasonic cleaning on the surface of the mining metal top beam, removing oxide skin, greasy dirt and impurities on the surface, and performing hot air drying treatment after cleaning until the surface shows metallic luster; S3, boxing and sealing, namely paving a layer of the multi-component co-penetrating agent prepared in the step S1 at the bottom of a stainless steel infiltration box, wherein the thickness is 20-30 mm, putting the mining metal top beam processed in the step S2 into the infiltration box, filling the rest multi-component co-penetrating agent around and at the top of the top beam, vibrating the infiltration box to eliminate powder gaps and ensure that the co-penetrating agent is in close contact with the surface of the top beam, and then sealing and packing the infiltration box by adopting refractory clay or water glass mixed sand; s4, gradient high-temperature chemical co-permeation, namely putting the sealed permeation box into a heating furnace, firstly heating to 600-650 ℃ for pre-permeation heat preservation for 1-2 hours, then heating to 880-920 ℃ at a heating rate of 5-10 ℃ per minute, and carrying out isothermal maintenance at the temperature for 4-6 hours to enable boron, carbon, chromium, sulfur and rare earth elements to diffuse into a matrix to form a gradient permeation layer; S5, cooling and quenching integrated treatment, namely after finishing heat preservation in the step S4, carrying out furnace cooling and homogenizing along with a furnace, reducing the temperature to 820-860 ℃, and carrying out austenitizing and homogenizing treatment after heat preservation for 30-60 minutes; s6, performing low-temperature tempering and stress removal, namely cleaning the quenched mining metal top beam, removing the co-penetrating agent and quenching oil remained on the surface, putting the mining metal top beam into a tempering furnace for heating, controlling the tempering temperature to be 200-400 ℃, preserving the heat for 1-2 hours, and then performing air cooling to room temperature; S7, post-treatment and detection, namely straightening the tempered mining metal top beam, and detecting surface hardness, depth of seepage and metallographic structure; in the step S1, the granularity of boron carbide powder, chromium powder and ferrous sulfide powder is controlled between 150 meshes and 200 meshes, and the granularity of rare earth magnesium silicon iron alloy powder is controlled between 200 meshes and 300 meshes; In the step S4, the temperature rising rate of heating from room temperature to 600-650 ℃ pre-infiltration temperature is controlled to 3-5 ℃ per minute so as to ensure the uniformity of the temperature field inside the infiltration tank.
  2. 2. The surface heat treatment process for improving the strength of the mining metal top beam according to claim 1, wherein the mechanical ball milling dispersion treatment in the step S1 is performed at a ball milling rotating speed of 200r/min-300r/min, the ball material mass ratio is 3:1-5:1, and the ball milling medium is stainless steel balls or zirconia balls.
  3. 3. The surface heat treatment process for improving the strength of a mining metal roof rail according to claim 1, wherein in step S5, the transfer time from opening the infiltration tank to completely immersing the mining metal roof rail in the quenching bath is controlled to be 30 seconds to 60 seconds.
  4. 4. The surface heat treatment process for improving the strength of a mining metal roof beam according to claim 1, wherein the tempering treatment in the step S6 is performed at a tempering temperature of 200 ℃ to 250 ℃ or 350 ℃ to 400 ℃.

Description

Surface heat treatment process for improving strength of mining metal top beam Technical Field The invention relates to the technical field of surface heat treatment, in particular to a surface heat treatment process for improving the strength of a mining metal top beam. Background The mine metal top beam is used as a key bearing member of the underground hydraulic support and is used in a severe environment with high dust, high humidity and acid water leakage for a long time, and in the coal mine mining process, the surface of the top beam is required to bear severe scraping and high contact stress of hard rock and also is faced with chemical erosion of underground circulating water. The surface treatment techniques currently in common use present significant limitations in dealing with such complex conditions. On the one hand, the existing hardening treatment means can only provide single performance improvement, and the impact toughness of the base body is difficult to be considered while the surface hardness of the top beam is improved. This results in the phenomenon that the top beam is liable to crack or even break as a whole due to excessive surface brittleness when subjected to a dynamic impact of sudden pressing against the top plate. On the other hand, the protective layer formed by the traditional process has insufficient chemical stability and weak corrosion resistance in the water environment of the acid mine, so that the top beam is extremely easy to pitting corrosion and local corrosion in actual use, and the long-term service life of the material is further weakened. In addition, as the bonding strength between the existing treatment layer and the base material is not ideal enough, under the heavy-load friction working condition, the protective layer often has peeling and abnormal loss, and continuous and stable safe support cannot be provided for the top beam. Disclosure of Invention The invention aims to provide a surface heat treatment process for improving the strength of a mining metal top beam, which solves the problems in the background technology. In order to solve the technical problems, the invention provides a surface heat treatment process for improving the strength of a mining metal top beam, which comprises the following steps: S1, preparing a multi-element co-permeation agent, namely weighing 40-60% of boron carbide powder, 3-8% of rare earth magnesium silicon iron alloy powder, 5-10% of chromium powder, 1-3% of ferrous sulfide powder, 3-5% of potassium fluoborate and the balance of aluminum oxide powder or silicon carbide powder as filler according to mass percent, placing the components into a ball mill for mechanical ball milling and dispersing treatment, controlling the ball milling time to be 2-4 hours, uniformly mixing and refining particles, and screening to obtain the multi-element co-permeation agent; s2, surface pretreatment of a base material, namely performing sand blasting rust removal and ultrasonic cleaning on the surface of the mining metal top beam, removing oxide skin, greasy dirt and impurities on the surface, and performing hot air drying treatment after cleaning until the surface shows metallic luster; S3, boxing and sealing, namely paving a layer of the multi-component co-penetrating agent prepared in the step S1 at the bottom of a stainless steel infiltration box, wherein the thickness is 20-30 mm, putting the mining metal top beam processed in the step S2 into the infiltration box, filling the rest multi-component co-penetrating agent around and at the top of the top beam, vibrating the infiltration box to eliminate powder gaps and ensure that the co-penetrating agent is in close contact with the surface of the top beam, and then sealing and packing the infiltration box by adopting refractory clay or water glass mixed sand; s4, gradient high-temperature chemical co-permeation, namely putting the sealed permeation box into a heating furnace, firstly heating to 600-650 ℃ for pre-permeation heat preservation for 1-2 hours, then heating to 880-920 ℃ at a heating rate of 5-10 ℃ per minute, and carrying out isothermal maintenance at the temperature for 4-6 hours to enable boron, carbon, chromium, sulfur and rare earth elements to diffuse into a matrix to form a gradient permeation layer; S5, cooling and quenching integrated treatment, namely after finishing heat preservation in the step S4, carrying out furnace cooling and homogenizing along with a furnace, reducing the temperature to 820-860 ℃, and carrying out austenitizing and homogenizing treatment after heat preservation for 30-60 minutes; s6, performing low-temperature tempering and stress removal, namely cleaning the quenched mining metal top beam, removing the co-penetrating agent and quenching oil remained on the surface, putting the mining metal top beam into a tempering furnace for heating, controlling the tempering temperature to be 200-400 ℃, preserving the heat for 1-2 hours, and then performing