| Power hacksaw blade is made of high-speed steel and bi-metalic metals. However, the high-speed steel consumes a great deal of alloying elements and the bi-metalic saw has difficulties in alloying and complexities in the processes. The above problem can be solved by surface alloying high-speed steel which is made from Double Glow Plasma Surface Alloying Technique. By using DGPSAT, the alloy layer with special physical, chemical and mechanical performance can be obtained on the surface of metallic materials. Moreover,the content of alloying metals in the surface can approach that of high-speed steel. After quenching and tempering, a good comprehensive mechanical properties can be achieved. In these experiments, power hacksaw blade 20Cr2V2 actes as the sample to have heat treatment after metal alloying and carborizing. Then engage in the research of technologies and performance. All these work are expected to explore the industrializing application of the surface high-speed steel power hacksaw blade.Six blocks in the same metal-alloying process are treated in different carbon potentials, different quenching temperatures and different tempering temperatures. Three carbon potentials, two quenching methods, three quenching temperatures, five tempering temperatures can finally lead to different tempering curves. From these curves, we cancompare the different tempering performance to each other. The comparative involved the different carbon content's tempering hardness on the same quenching temperature process and the different quenching temperature process on the same carbon contents. The metallograph and X-raydiffraction method were used to analyze structures. Then wear testing are used to compare the different samples after quenching and tempering in 550 ℃ and the sample of high-speed steel during 2 hours and under 1250N.The results indicate that the depth of alloying layer are between 30μ m and 150μm on the surface of blade 20Cr2V2.f he surface material's alloying content is between 10% and 40% by DGPSAT. The carborizing surface has different carbon contents with different Carbon potentials. The carbon potential which is higher than the balance carbon principle is not easy to come into being network carbide. The different influences in the different carbon potentials of a fixed quenching temperature are that the higher is the quenching temperature ,the higher is the quench's tempering hardness. The interrupted quenching's hardness curves are a little lowerthan the oil quenching's hardness in three carbon potentials. The different influences in the different quenching temperatures of a fixed carbon potential is that, the hardness of oil quench in 0.7% carbon potential is rising with temperature, there is obvious secondary hardening in 0.7%carbon poential. With the carbon potential's rising, the temperature's influence is more crutial, so the hardness after 1200 ℃ oil quench in the 1.35% potential is highest The gap between oil quench and interrupted quenching is obvious. The influence of quenching method on hardness after tempering is due to alloying carbide's amount. The amount in interrupted quenching is big, so it can delay Martensite's transformation.The wear and tear test shows that the material hardness and surface condition have a crucial influence on the wear performance. In this wear experiment, the higher is the hardness and the more smooth is the surface , the smaller is the wear quantity. Wear quantity is decided by the surface and the hardness. Comparing the surface alloy's high-speed steel to WeMo5Cr4V21 the more similar is the hardness, themore similar is the wear quantity. In the same hardness, the more rougher is the surface, the biger is the cof The biger cof is owing to the micro cutting under the condition of oiling. The higher hardness and rougher surface lead to a hard microcutting , so the cof is big. The surface in the higher hardnessis separate cut, but the surface in the lower hardness is an area owing to a lot of cuts gather...
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