Martensitic age-aged steel has good hot plasticity at high temperatures, and its hot workability is roughly the same as that of 1Cr18Ni9Ti. For steel grades with a relatively high content of titanium and molybdenum, microscopic segregation of these elements is prone to occur during the solidification of steel ingots, and an anisotropic banded microstructure is formed after hot working. Effective measures to alleviate or eliminate microscopic segregation are to select the appropriate size of steel ingots and carry out sufficient high-temperature homogenization treatment during hot working. To prevent high-temperature slow cooling brittleness caused by the precipitation of compounds such as Ti(C, N) along the austenite grain boundaries, after hot working, it is advisable to avoid slow cooling or holding the workpiece within the temperature range of 1100 to 750 ° C as much as possible. In order to obtain fine grains and better mechanical properties, the final forging should be completed at a relatively low temperature (950-850 ° C) with a large deformation (more than 25%).

American 18Ni steel is a representative steel grade of martensitic aging steel. It is classified into four grades according to the value of tensile strength (unit: KSI, 1KSI=6.89476MPa) :

Product Introduction

Chemical composition（%）

Application field

Due to its excellent comprehensive performance, martensitic age-hardening steel can be used to manufacture various tools and molds, such as injection molds and die-casting molds, which can increase the service life of molds and product quality. In the field of mechanical engineering, components such as crankshafts made of martensitic age-hardening steel can withstand large loads and complex stresses, ensuring the stable operation of mechanical equipment.

In the military field, martensitic age-hardening steel is widely used in rocket engine casings, missile components, etc. Its high strength and good toughness can meet the usage requirements of military equipment under extreme conditions and improve the performance and reliability of weapon systems.