China's current general wear-resistant materials have the following major series:
One is high manganese steel series: such as high manganese steel (ZGMn13),
High manganese alloy (ZGMn13Cr2MoRe), ultra high manganese alloy (ZGMn18Cr2MoRe), etc.;
Second, wear-resistant chromium cast iron series: such as high, medium and low chromium alloy cast iron (such as Cr15MOZCu);
The third is wear-resistant alloy steel series: such as medium, low, high carbon multi-material steel (such as ZG40SiMnCrMO and ZG35Cr2MoNiRe);
The fourth is the ADI series;
Fifth, all kinds of composite or gradient materials and hard alloy materials: such as chromium carbide composite materials (Cr2C3+Q235), high-energy ion implantation tungsten carbide materials (WCSP), high toughness hard alloy (YK25.6), etc.; Is a variety of non-metallic wear-resistant materials: such as polymer ceramic composites, silicon nitride (Si3N4), toughened zirconia (Y2O3 + ZrO2), toughened aluminum oxide (Al2O3/ZrO2), etc.. Different series of wear-resistant Material properties comparison:
2.2.1 High-manganese steel series: It is represented by high-manganese steel ZGMn13. Under severe impact or contact stress, its surface will quickly harden, while the core still maintains extremely strong toughness. The external hard internal toughness is both anti-wear and anti-reaction. Impact. And the heavier the surface, the harder the surface hardening, the better the wear resistance. Due to the low hardness of high manganese steel (HB170-230), the wear resistance is extremely limited when it is not hardened. Manganese steel parts under the impact of the impact, the surface can not be fully hardened (fully hardened surface hardness up to HB550, otherwise below the HB350 below) the wear resistance can not be played, and showed no wear.
2.2.2 Anti-abrasion high-chromium cast iron series: According to the organizational structure and use conditions, chromium cast iron can be divided into three categories: The first type is chromium-based white cast iron with good high temperature performance. The cast iron contains 33 chromium. %, most of its organization is austenitic and iron-chromium carbide, and sometimes ferrite. In addition to this alloy has a certain degree of wear resistance, in the high temperature working conditions of temperature not higher than 1050 °C, it has good Antioxidant properties. The second category is chromium-based white cast iron with good wear resistance (referred to as high-chromium cast iron). In addition to containing 12 to 20% of chromium, the cast iron contains an appropriate amount of molybdenum. This type of cast iron solidifies. After the organization of (Fe, Cr) 7C3 type carbide and γ phase. When the matrix is entirely martensite, the wear resistance of this alloy is the best. If there is residual austenite in the matrix, usually heat treatment. The third category is low chromium alloy white cast iron. Compared with ordinary white cast iron, the stability of carbides in this cast iron is better.[2]
2.2.3 Wear-resistant alloy steel series: It is divided into low-alloy steel, medium-high alloy steel, and wear-resistant alloy steel. Through the regulation of chemical composition and heat treatment process, necessary impact toughness and hardness index of the material can be obtained. The hardness can reach HRC. = 52 ~ 58 toughness can reach ak = 15 ~ 30J/cm2.
2.2.4 Abbott ductile iron (ADI) series: It is through the isothermal quenching heat treatment or the addition of alloying elements, so that the ductile iron matrix transformation from ferrite, pearlite to austenite, bainite and retained austenite. ADI has the following unique advantages: 1 high strength, good plasticity. 2 Flexural fatigue and contact fatigue, high dynamic load performance. ADI's rotary bending fatigue strength up to 400 ~ 500MPa, and quenched and tempered low alloy steel, ADI's Contact fatigue strength of up to 1600 ~ 2100MPa, higher than the low alloy steel nitriding treatment and carburizing treatment of contact fatigue strength. 3 good shock absorption. ADI due to low elastic modulus, plus graphite balls in the matrix, can quickly absorb vibration And increase the noise damping, make the parts run more quiet and smooth. 4 excellent wear and abrasion resistance. ADI's wear resistance, better than any steel with the same hardness level. 5 good processing performance: ADI large Some mechanical processing can be completed before the isothermal quenching, this time is generally ferrite ductile iron, its processing performance is significantly better than steel.
2.2.5 Composite or gradient material series: It is represented by high-energy ion-implanted tungsten carbide material (WCSP) and chromium carbide composite material (Cr2C3+Q235). The tungsten carbide material (WCSP) adopts high-energy ion implantation technology. The surface of the steel parts is infused with tungsten carbide (WC). WC and the steel substrate are metallurgically combined with complementary advantages. The surface has high hardness and high wear resistance of the WC. The core retains the original hardness of the selected steel substrate. , strength and toughness. There is also a graded gradient transition between the surface and the heart, which effectively avoids the material damage that may result when the performance changes.[3]
Carbide with hard alloy: Compared to high manganese steel and high chromium alloy steel, hammer carbide with higher hardness and wear resistance.
YK26.5: density: 14.58 (g/cm3); hardness (CHRA): 87.5; flexural strength: 2650 (MPa); fracture toughness: 12 - 16 (MPam1/2)
2.2.6 Non-metallic Wear Resistant Material Series
There are many types of non-metallic wear-resistant materials, including ceramic composites, silicon carbide (SiC), silicon nitride (Si3N4), toughened zirconia (Y2O3+ZrO2), and toughened alumina (Al2O3/ZrO2). Wait.
Ceramic composite materials: Ceramics are crystalline or non-crystalline compounds composed of metallic and non-metallic elements, with high melting point, high hardness, strong rigidity, and good chemical stability. The wear-resistant ceramic coating is a non-metallic cementitious material, which is used Acid-resistant and alkali-resistant synthetic powdered ceramic material.
Features:
(1) High mechanical strength and rigidity: high density, strength up to 130Mpa, can effectively resist the impact force and shear stress of the material.
(2) Excellent toughness and shock resistance: As the ceramic wear-resistant material adopts non-directional rigid fibers and oriented mesh reinforcement measures, the toughness is further improved through coupling, so the fracture toughness is strong, and the damage and peeling caused by the impact force can be effectively prevented.
(3) Good environmental compatibility.[4]
Toughened ceramic: It is represented by toughened zirconia (Y2O3+ZrO2), toughened aluminum trioxide (Al2O3/ZrO2) and other structural ceramics. It has wear resistance, corrosion resistance, high temperature resistance, high strength, high hardness Etc.
It can adapt to the unbearable environment and working conditions of metal and polymer materials. The specific indicators are as follows:
Material Strong Zirconium Oxide Strong Aluminum Oxide Silicon Nitride
Composition Y2O3+ZrO2 Al2O3/ZrO2 Si3N4
Density g/cm3 6—6.05 3—4.5 3.2
Hardness CHRA 89 85 - 88 93
Flexural strength MPa1000-1200 300-500 900
Fracture toughness MPam1/212—14 5—7 8.5
