Hot Rolled Steel Round Bar Hot Rolled Alloy Bar 18Crnimo7-6 Equivalent Astm

The failure cause of the 18CrNi3Mo steel for drilling bit, including inclusions, prior austenite grain size, carburized layers, and morphology of the fatigue fracture, was investigated by optical microscope, quantitative metallography, and scanning electron microscope. Results show that the failure of the drill bit is not related to interior inclusions or the inhomogeneity of the prior austenite grain size distribution. The failure is related to geometrical discontinuities causing stress concentration along the tooth profiles while under effect of continuous twisting and axial impact. Thus, the crack initiates in these areas, and the microstructures of the carburized layer, the transitive layer, and the matrix are all tempered martensite such that the crack propagation cannot be effectively restrained and the crack propagates quickly, causing premature failure of the drilling bit.

Jiangsu Mittel Steel Industrial Limited is  located in Wuxi City,  a beautiful city near Shanghai.  Wuxi is close to  Shanghai (BAO STEEL) ,Zhangjiagang (ZPSS),Ningbo (BAO XIN),KUN SHAN (DKSS), enjoy excellent geographic location and convenient water, land and air transportation. , Wuxi become the biggest  stainless steel sheet ,plate and coil  supply Centers in China. Jiangsu Mittel Steel Industrial Limited was established in 1998 years. as one of the largest stockists and manufacturers of industrial grade Stainless Steel products and derivatives in Wuxi ,We keep a stock of 50000 tons every month, so we can delivery goods in fast time.

Our company supplies cold/hot-rolled stainless steel sheets,stainless steel coils and stainless steel Plate to many steel factories from athome and abroad, including Shanxi Taigang Iron& Steel CO, . Ltd (TISCO)Zhangjiagang Pohang (ZPSS), Shanghai BAO STEEL, Ningbo Baoxin and steel factories in Taiwan area, Mainland Chinese and foreign countries and regions. 

Our long-term business lines are 201.202.304(1.4301).304L.316.316L(1.4404).430.409L, 309S ,310S(1.4845).317L.904L.S31803(1.4462).S32750.S32760, Finish: 2B, BA, NO. 1 NO. 4, HL, 8K and so on...Meanwhile, our company is also engaged in the long-term supply of homemade & imported medium and thick plates, galvanized and carbon steel products. 

Adhering to the principle of "quality first and customer foremost",our company will offer long-term service to nationwide manufacturers of household appliances, elevators, tableware, ornaments, tanks and machines. We can offer precise frosted wiredrawing, 8K mirror finishing and skim board oil-abrasion of various specifications at any time. The precisely-processed products will meet your requirements for high quality. Our company is a modern enterprise integrating distribution and storage. 

If you are interested in any of our products or would like to discuss a custom order, please feel free to contact us. We are looking forward to forming successful business relationships with new clients around the world in the near future.