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Ling Feng wear-resistant materials introduction
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China's current general wear-resistant material has the following several major series:A series of high-manganese steel: such as high manganese steel ( ZGMn13 ),High manganese alloy ( ZGMn13Cr2MoRe ), the super high manganese alloy ( ZGMn18Cr2MoRe ) etc.;Two is a wear-resistant chromium cast iron series: high, low chromium alloy cast iron ( such as Cr15MOZCu );Three wear resistant alloy steel series: such as, low, high carbon multiple gold Hegang ( such as ZG40SiMnCrMO and ZG35Cr2MoNiRe );Four is the austempered ductile iron ( ADI ) series;Five types of composite or gradient material and hard alloy materials: such as chromium carbide composite material ( Cr2C3+Q235 ), a high-energy ion permeability of tungsten carbide materials ( WCSP ), high toughness of cemented carbide ( YK25.6 ); six types of non-metallic wear-resistant materials: such as polymerization ceramic composites, silicon nitride ( Si3N4 ), toughening and oxidation zirconium ( Y2O3+ZrO2 ), toughening of three two aluminum oxide ( Al2O3/ZrO2 ) etc.. Performance comparison of different series of wear-resistant materials:2.2.1 series of high-manganese steel: the representative of ZGMn13 high manganese steel. In the intense impact or contact stress, its surface will rapidly hardened, while the core remains strong toughness, hard outer inner tough both abrasion resistance and impact. And the surface is affected by the impact of heavier, more fully hardened surface, wear resistance is better. Due to its very low hardness of high manganese steel ( HB170-230 ), before hardening when wear resistance is extremely limited, if the high manganese steel parts surface to bear impact force is insufficient, cannot be fully hardened surface ( fully hardened surface hardness can reach HB550 and above, or below HB350), abrasion resistance and can not play, and show don't wear condition.2.2.2 high-chromium cast iron series : according to the structure and usage, chromium cast iron can be divided into three categories: the first category for having good high temperature properties of chromium white cast iron. The cast iron chromium content of 33%, the majority of organization for austenitic and Fe-Cr carbides, also appear sometimes ferrite. This alloy has certain wear, at a temperature not higher than 1050 DEG C high temperature working conditions, it has good oxidation resistance. Second kinds of good wear resistance of chromium white cast irons ( referred to as the high chromium cast iron ). The cast iron in addition to containing 12～20% chromium, also containing molybdenum. This type of cast iron solidification organization for ( Fe, Cr ) 7C3 type carbides andγ phase. When the matrix is all for martensitic alloy, the best on the wear resistance. If the matrix is present in the residual austenite, usually by heat treatment. Third types of low chromium white cast iron. Compared with ordinary white cast iron, the iron carbide better stability. 2.2.2.3 wear-resistant alloy steel series: is divided again for low alloy steel, high alloy steel, medium. Wear resistant alloy steel through the regulation of chemical composition and heat treatment process to obtain the necessary material impact toughness and hardness index. Hardness up to HRC=52 ～ 58, toughness can reach ak=15～ 30J/cm2.2.2.4 austempered ductile iron ( ADI ) series: it is through the Austempered or addition of alloying elements, the ductile iron matrix is composed of ferrite, pearlite to austenite, bainite and residual austenite. ADI has the following unique advantages:① high strength, good plasticity. The bending fatigue and contact fatigue and dynamic properties of high. ADI rotating bending fatigue strength of 400 ～ 500MPa, and Tempered Low-Alloy Steel, ADI contact fatigue strength of 1600 ～ 2100MPa, than low alloy steel nitriding and carburizing of contact fatigue strength. The shock absorption is good. ADI due to a low modulus of elasticity, coupled with the substrate in graphite, can rapidly absorb shock and increased noise damping, so that the components of the more quiet and smooth operation. The excellent wear resistance, wear resistance. ADI abrasion resistance, hardness than any equivalent levels of steel are good. The good processing performance: most ADI machining can be completed before isothermal quenching, the general for the ferrite ductile iron, its processing performance was significantly better than steel.2.2.5 composite or gradient materials series: its representative is a high-energy ion permeability of tungsten carbide material ( WCSP ) and chromium carbide composite materials ( Cr2C3+Q235 ). Tungsten carbide material ( WCSP ) is the use of a high-energy ion permeability technology to steel parts surface implanted WC steel matrix .WC ( WC ) and two are metallurgy combination, complementary advantages. Surface has WC high hardness, high wear resistance. The heart has retained the selected steel matrix hardness, strength and toughness of the original. In the surface layer and center of have a functionally gradient gradient transition zone, effectively avoids performance mutation may cause material damage. 3.Hammer with a hard alloy: relative to the high manganese steel and high chrome alloy steel, hammer with a cemented carbide has a high hardness and wear resistance of.The density of YK26.5:: 14.58 ( g/cm3 ); hardness ( CHRA ): 87.5; bending strength: 2650 ( MPa ); fracture toughness ( MPam1/2 ): 12 -- 162.2.6 non-metallic wear-resistant material seriesNon metal materials of many kinds, on behalf of the material with ceramic composites, silicon carbide, silicon nitride ( SiC ) ( Si3N4 ), toughened zirconia ( Y2O3+ZrO2 ), toughening of three two aluminum oxide ( Al2O3/ZrO2 ) etc..Ceramic composite materials: ceramic metal and non-metallic elements consisting of a crystal or amorphous compounds, high melting point, high hardness, strong rigidity, good chemical stability. Abrasion resistant ceramic coating is a kind of nonmetallic cementing material, it is the use of acid and alkali of synthetic powdered ceramic material.Characteristic.( 1) a high mechanical strength and stiffness: density, strength of up to 130Mpa, can effectively resist the impact force of material and shear stress.( 2) good toughness and shock resistance: due to wear-resistant ceramic materials adopted without orientation just fiber and directional reticular reinforcing measures, through the coupling to further improve the toughness, so the fracture toughness, can effectively prevent the damage caused by impact force and flaking off.( 3) good environmental compatibility ( 4 ).The strengthening and toughening ceramic: its representative for toughened zirconia ( Y2O3+ZrO2 ), toughening of three two aluminum oxide ( Al2O3/ZrO2 ) and other structural ceramics. Has the wearability, corrosion resistance, high temperature resistance, high strength, high hardness and other advantages.Can be adapted to the metal and polymer materials difficult to sustain the environment and working conditions. Specific indicators are as follows:Material toughness zirconia toughening three two aluminum oxide silicon nitrideComposition of Y2O3+ZrO2 Al2O3/ZrO2 Si3N4The density of g/cm3 6 -- 6.053 -- 4.5 3.2Hardness of CHRA 8985 -- 8893Flexural strength of MPa1000 - 1200300 - 500900Fracture toughness of MPam1/212 - 145 - 78.5
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