Quenched and tempered nm550 steel wear resistance specs
How to prevent NM550 steel wear resistance, steel plate cutting cracks? 1. Preheat the steel plate before cutting, and the preheating temperature depends on the quality grade and thickness of the steel plate. However, it needs to be heated evenly. 2. The cutting speed is reduced appropriately, but its reliability is not as good as preheating. It is suggested to preheat the cutting belt with flame gun cavitation several times before cutting, and the preheating temperature should reach about 180℃.
For wear-resistant steel plate, it is not the higher the hardness, the better the wear resistance! Hardness is the basis of excellent wear resistance of NM550 steel wear resistance, wear-resistant steel plate, but the relationship between hardness and wear resistance is not in direct proportion. The reason why wear-resistant steel plates are wear-resistant is that they have hard particles and soft matrix. Generally, in the process of wear, there will be some falling substances, which will be incorporated into the soft matrix and will not cause great damage to the surface.
A small amount of Nb is sufficient to obtain excellent comprehensive properties of NM550 steel wear resistance etc. steel material, because at low Nb concentration, the yield strength of steel material increases faster and is proportional to the concentration, but when the Nb content is greater than 0.03%, the strengthening effect begins to decrease. Studies have shown that when the Nb content is greater than 0.06%, excess Nb will no longer strengthen the steel material.
The "Plan" pointed out that by the end of December 2020, the steel production capacity in Tianjin will be controlled at about 15 million tons, and the steel production capacity in Hebei Province will be controlled within 200 million tons, and the elimination of the carbonization chamber with long furnace age and poor furnace condition will be accelerated. 4.3 Rice coke ovens promote the gradual withdrawal of independent coking companies. At present, there are 24 steel enterprises in Shanxi Province in need of transformation, of which 17 have been completed, and the remaining 7 enterprises are speeding up project-related finishing work.