abrasion resistant steel plate, the higher hardness, the better wear resistance ?

At present, the wear resistant materials national standard often take hardness as the basis. Many of these views in traditional social theory, all said that the abrasion resistant steel plate will has an outstanding wear resistance if the hardfacing layer has a high hardness, so we will always make this note ( hardfacing layer hardness must greater than a specified value) on our equipment production drawings. And actually, hardfacing material of high hardness is not necessarily good, there is not a consistent one-to-one match between the hardness and wear resistance.

Tungsten carbide has a high melting point, high hardness and good stability, which is the most excellent wear abrasion material.

During the abrasive wear test, the abrasive wear weight loss decreased almost linearly when tungsten content increasing from 3.26% to 6.15%, and weight losses became  slowing down when tungsten content increasing from 6.15% to 8.26%, the surfacing layer weight loss is only 0.097 G when tungsten content reaches at 8.26%.

The tungsten is a carbide forming element stronger than chromium,and can form WC, W2C hard phase with carbon, tungsten carbide content kept rising with the increase of tungsten content, tungsten carbide has high abrasive wear resistance, so the abrasive wear resistance of hardfacing layer was increased. The carbide hard phase will not  increase any more because hardfacing layer has limited Carbon. Combining the hardness test,the hardness value is not proportional to the wear resistance.