阅读说明：本技术 一种提高钢丝钳剪切刃口强韧性的方法 (Method for improving toughness of cutting edge of wire pliers ) 是由 张永军 于 2020-06-30 设计创作，主要内容包括：一种提高钢丝钳剪切刃口强韧性的方法,属于钢铁材料加工技术领域。其特征在于本发明主要通过对碳钢材质的钢丝钳进行淬火、高温回火的调质热处理,以及对钢丝钳剪切刃口进行滚压处理来获得具有较高强韧性的钢丝钳剪切刃口。通过调质热处理保证了钢丝钳剪切刃口心部具有一定的强度和良好的韧性,克服传统工艺制备的剪切刃口韧性不足而引起的易崩刃问题；通过滚压使剪切刃口表层形成明显的塑性强化层及其晶粒的细化,进而实现刃口的强化；因此,相对于按照传统方法制备的同材质钢丝钳剪切刃口,其强度、硬度可提高60％以上,进而提高了刃口的耐磨损性能。总之,本发明将有助于提高碳钢材质钢丝钳的市场竞争力。(A method for improving the obdurability of a cutting edge of a cutting pliers belongs to the technical field of steel material processing. The method is characterized in that the cutting edge of the wire pliers with high strength and toughness is obtained by quenching and tempering heat treatment of high-temperature tempering on the wire pliers made of carbon steel and rolling the cutting edge of the wire pliers. The center of the cutting edge of the wire pliers is ensured to have certain strength and good toughness through quenching and tempering heat treatment, and the problem of easy tipping caused by insufficient toughness of the cutting edge prepared by the traditional process is solved; the surface layer of the shearing blade forms an obvious plastic strengthening layer and refines grains thereof through rolling, thereby further realizing the strengthening of the cutting edge; therefore, compared with the cutting edge of the wire cutter made of the same material and prepared by the traditional method, the strength and the hardness of the cutting edge can be improved by more than 60 percent, and the abrasion resistance of the cutting edge is further improved. In a word, the invention is beneficial to improving the market competitiveness of the pliers made of carbon steel.)

1. The method for improving the obdurability of the cutting edge of the wire pliers is characterized by comprising the following main chemical components in percentage by mass: 0.42-0.50% C; 0.20-0.50% Si; 0.50-0.80% Mn; p is less than or equal to 0.025 percent; the preparation process of the carbon steel wire pliers with S less than or equal to 0.025% mainly comprises forging, machining, heat treatment, grinding wheel polishing, rolling, assembling, surface treatment and the like. Wherein the heat treatment mainly refers to quenching and tempering heat treatment of quenching and high-temperature tempering; the rolling refers to rolling plastic deformation of the surface of the shearing cutting edge at room temperature by using a roller.

2. The method for improving the toughness of the cutting edge of the wire cutter as claimed in claim 1, wherein: the heat treatment is quenching and tempering heat treatment of quenching and high-temperature tempering on the forged and machined blank, wherein the quenching temperature is 830-850 ℃, and the heat preservation time is 3-5 min/mm; the high-temperature tempering temperature is 510-530 ℃, and the heat preservation time is 4-6 min/mm; the method aims to obtain a good tempered sorbite structure through quenching and tempering, so that the center of a cutting edge of the cutting pliers is ensured to have certain strength and good toughness, and the problem that the toughness is insufficient during medium-temperature and low-temperature tempering adopted in the traditional process, and the problem that the cutting edge is easy to break is solved.

3. The method for improving the toughness of the cutting edge of the wire cutter as claimed in claim 1, wherein: the rolling is to perform three rolling treatments on the blank after forging, machining, heat treatment and grinding wheel polishing, wherein the width of the adopted roller is 1-2 mm larger than that of the shearing cutting edge; the rolling reduction of the first rolling is 2-3% of the average thickness of the finished product of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.06-0.10 mm/s; the rolling reduction of the second pass rolling is 1-2% of the average thickness of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.08-0.12 mm/s; the rolling reduction of the third rolling is 0.3-0.5% of the average thickness of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.12-0.15 mm/s; the purpose of the three-pass rolling is to form an obvious plastic strengthening layer on the surface layer of the shearing blade edge through rolling and refine grains of the shearing blade edge, so that the strengthening of the cutting edge is realized.

4. The preparation method for improving the toughness of the cutting edge of the wire cutter as claimed in claims 1, 2 and 3, wherein the preparation method comprises the following steps: the cutting edge of the cutting wire pliers processed according to the method disclosed by the application has the advantages that the toughness required by the cutting edge is ensured due to the fine and uniform tempered sorbite structure at the center of the cutting edge; the rolling plastic deformation of the surface layer and the refinement of crystal grains ensure the strength required by the cutting edge; compared with the cutting edge of the cutting wire pliers made of the same material and prepared by the traditional method, the grain size of the surface layer can be reduced by more than 50 percent; the strength and the hardness can be improved by more than 60 percent.

Technical Field

The invention relates to a method for improving the obdurability of a cutting edge of a wire cutter, belonging to the technical field of steel material processing.

Background

The wire cutter is a common hardware tool for cutting various steel wires, electric wires and the like, and is widely applied in work and life. When the wire pliers shear the steel wire, the shearing edge part bears the shearing force, and the requirements of high strength, low brittleness and good abrasion resistance are met. Namely, the shearing cutting edge is required to have higher toughness and wear resistance.

To meet this requirement, the methods currently used are mainly carried out by heat treatment methods of quenching, medium-temperature or low-temperature tempering. However, the heat treatment method is difficult to obtain higher strength and hardness for the wire cutters made of carbon steel, and particularly, the wire cutters made of carbon steel with lower carbon content often have rolling edges and pits to lose effectiveness; or the carbon content of the carbon steel is increased, but the strength is improved, but the toughness is reduced, and the carbon steel is often broken during shearing to lose effectiveness. In a word, the quality of the wire pliers made of carbon steel is at a low level, and the market competitiveness is not high.

In order to improve the quality of the carbon steel wire pliers, namely the strength and toughness of the carbon steel wire pliers, the high strength and toughness of the shearing cutting edge is realized by quenching, heat treatment of high-temperature tempering and rolling treatment of the shearing cutting edge of the wire pliers made of medium carbon steel. At present, the method is not reported in the literature in a public way.

Disclosure of Invention

A method for improving the toughness of the cutting edge of a cutting wire pliers is mainly realized by quenching and tempering heat treatment of high-temperature tempering on the cutting wire pliers made of carbon steel and rolling the cutting edge of the cutting wire pliers.

The invention is realized by the following technical measures:

the method for improving the toughness of the cutting edge of the wire cutter is characterized by mainly comprising the following steps:

the method for improving the obdurability of the cutting edge of the wire pliers is characterized by comprising the following main chemical components in percentage by mass: 0.42-0.50% C; 0.20-0.50% Si; 0.50-0.80% Mn; p is less than or equal to 0.025 percent; the wire pliers are made of carbon steel with S less than or equal to 0.025 percent; the process is mainly carried out according to the sequence of working procedures such as forging, mechanical processing, heat treatment, grinding wheel polishing, rolling, assembling, surface treatment and the like. Wherein the heat treatment mainly refers to quenching and tempering heat treatment of quenching and high-temperature tempering; the rolling refers to rolling plastic deformation of the surface of the shearing cutting edge at room temperature by using a roller;

further, the heat treatment is quenching and tempering heat treatment of quenching and high-temperature tempering on the forged and machined blank, wherein the quenching temperature is 830-850 ℃, and the heat preservation time is 3-5 min/mm; the high-temperature tempering temperature is 510-530 ℃, and the heat preservation time is 4-6 min/mm; the purpose is to obtain a good tempered sorbite structure through quenching and tempering treatment, and further ensure that the center of the cutting edge of the cutting pliers has certain strength and good toughness. The problem of poor toughness during medium and low temperature tempering adopted in the traditional process is solved, and the problem of easy edge breakage is further solved.

Further, the rolling is to perform three rolling treatments on the blank after forging, machining, heat treatment and grinding wheel polishing, wherein the width of the adopted roller is 1-2 mm larger than that of the shearing cutting edge; the rolling reduction of the first rolling is 2-3% of the average thickness of the finished product of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.06-0.10 mm/s; the rolling reduction of the second pass rolling is 1-2% of the average thickness of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.08-0.12 mm/s; the rolling reduction of the third rolling is 0.3-0.5% of the average thickness of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.12-0.15 mm/s; the purpose is to form an obvious plastic strengthening layer on the surface layer of the shearing blade by rolling, so that grains are refined, and further the strengthening of the cutting edge is realized.

The invention has the beneficial effects that:

the cutting edge of the cutting wire pliers processed according to the method guarantees the toughness of the cutting edge through quenching and tempering heat treatment, grains on the surface layer of the cutting edge are refined and even nanocrystallized through rolling, compared with the cutting edge of the cutting wire pliers made of the same material and prepared according to the traditional method, the strength and hardness of the cutting edge of the cutting wire pliers can be improved by more than 60%, the wear resistance of the cutting edge of the cutting wire pliers made of carbon steel is further improved, the hardness and wear resistance close to those of the cutting edge of the cutting wire pliers made of chrome vanadium steel and prepared according to the traditional processing method can be even achieved, and the market competitiveness of the cutting wire pliers made of carbon steel.

Detailed Description

Embodiments of the present invention will now be described in detail.

The invention provides a method for improving the toughness of a cutting edge of a cutting pliers, which is mainly carried out according to the following steps:

(1) the main chemical components and the mass percentage content are as follows: 0.42-0.50% C; 0.20-0.50% Si; 0.50-0.80% Mn; p is less than or equal to 0.025 percent; the wire pliers are made of carbon steel with S less than or equal to 0.025 percent; the grinding wheel is mainly prepared by the processes of forging, machining, heat treatment, grinding wheel polishing, rolling reinforcement, assembly, surface treatment and the like;

(2) quenching and tempering heat treatment of quenching and high-temperature tempering is carried out on the forged and machined blank, wherein the quenching temperature is 830-850 ℃, and the heat preservation time is 3-5 min/mm; the high-temperature tempering temperature is 510-530 ℃, and the heat preservation time is 4-6 min/mm;

(3) carrying out three-time rolling treatment on the blank subjected to forging, machining, heat treatment and grinding wheel polishing, wherein the width of an adopted roller is 1-2 mm larger than that of a shearing cutting edge; the rolling reduction of the first rolling is 2-3% of the average thickness of the finished shearing blade (the average thickness of the shearing blade is the average value of the maximum thickness and the minimum thickness of the blade, the same is applied below), and the rolling linear speed of the roller along the surface of the blade is 0.06-0.10 mm/s; the rolling reduction of the second pass rolling is 1-2% of the average thickness of the shearing cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.08-0.12 mm/s; the rolling reduction of the third rolling is 0.3-0.5% of the average thickness of the shearing cutting edge, the average thickness of the shearing cutting edge is the average value of the maximum thickness and the minimum thickness of the cutting edge, and the rolling linear speed of the roller along the surface of the cutting edge is 0.12-0.15 mm/s.

The technical solution of the present invention is further described with reference to the following examples. The examples are intended to illustrate the invention only and are not intended to limit the invention in any way.