NM400 is one kind of Chinese wear/abrasion resistant steel plates, which is well received in middle east and Africa. An NM400 wear-resistant steel was hot rolled and then the plates were heat-treated by direct quenching and tempering and reheat quenching and tempering techniques, respectively. The impact test was carried out with an instrumented impact tester. The micro-structure and fracture surface were investigated by a combination of optical microscopy, transmission electron microscopy and scanning electron microscopy methods.

NM400 is a high-strength wear-resistant steel plate. NM400 has quite high mechanical strength,its mechanical properties are 3 times to 5 times that of ordinary low-alloy steel plates, it can significantly improve the wear resistance of mechanical-related components, thus increase the service life of machinery, reduce production costs. The surface hardness of this product usually reaches 360～450HB.