When 35CrMo seamless steel pipe at the time of 500HB hardness less, which is proportional to the tensile strength and hardness, kg / mm2 (óB) = 1/3 X HB = 3.2 X HRC = 2.1 X HS, but the above relation is not in What places have been established from heat side, the tempering temperature is low, kg / m㎡ correlation between HRC and can be destroyed when, 35CrMo hardness relationship seamless steel tempering temperature, hardness and tensile strength with the return temperature decreases with fire, but in the state and below 300 ℃ quenching and tempering, the relationship between hardness and tensile strength is difficult to set up. When the tempering temperature is about 300 ℃, kg / mm2 and a correlation between the HRC, namely high hardness, tensile strength is high; low hardness, tensile strength is low. In tempering state desires a kg / m㎡ value is difficult t91, because the tensile strength values ??are discrete distributions. Because kg / mm2 tempering 35CrMo unstable and can not be determined a seamless steel tube, so the Japanese Industrial Standard (JIS) in the tensile properties measured above 400 ℃ temperature tempering member also pass the test (also 300 ℃ tempered workpiece). In other words is reversed only quality pieces (+ 400 ℃ quenching and tempering) tensile test. Requirements in the industry just in the anti-rotating bending fatigue and abrasion resistance when using tempering pieces. Induction hardening and carburizing application examples that do this. 35CrMo seamless steel tensile stresses do not use low-temperature tempering. However, in low carbon steel alloy t91 51X3.5, but can occur since the quenching and tempering M (Ms point so high), there are users in the quenched state. Lath martensite structure of low carbon steel self-tempering, are applicable Tianjin t91 alloy pipe in the industry, but this time must be considered 35CrMo seamless steel hardenability and mass effect (if necessary add B, Cr, Mn and other metals). T91 steel pipe is a steel pipe, T91 steel in the United States as a tree Ridge National Laboratory and the US Combustion Engineering Metallurgical Materials Laboratory cooperation in the development of the new martensitic steel. It is based on 121MoV reduce the carbon content of steel on steel, Baosteel t91, strictly limit the content of sulfur, phosphorus, and add a small amount of vanadium, niobium alloying elements. According ASTM213 / A213M-85C, the chemical composition of T91 steel in Table 1. T91 steel and the corresponding number of German steel X10CrMoVNNb91, Japanese steel for HCM95, France was TUZ10CDVNb0901. Table 1 T91 steel chemical composition% t91 alloy steel pipe _t91_ Katherine source provided by the source Pipe Co., Ltd. Liaocheng trillion. Liaocheng Katherine source Pipe Co., Ltd. (www.lczygg.com) strong, credible, Liaocheng in Shandong steel industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving Katherine source of innovative ideas will lead pipe and you work into the brilliant, for a better future!