What Is Abrasion Resistant Steel?

A general term for iron and steel materials with strong wear resistance, wear-resistant steel is the largest amount of wear-resistant materials available today.

There is currently no uniform definition of "wear". It is generally believed that wear and tear is the phenomenon of continuous damage or loss of material on the working surface of an object in relative motion. There are also many methods for the classification of wear. If it is divided according to the wear mechanism, it can be divided into

1. The steel plate cutting method is suitable for cold cutting and hot cutting. Cold cutting includes water jet cutting, cutting, sawing or abrasive cutting; hot cutting includes oxygen fuel flame cutting (hereinafter referred to as "flame cutting"), isoparticle cutting, and laser cutting.

2. Cutting method: Through relevant process tests, grasp the general characteristics and cutting thickness range of various cutting methods for steel plates.

3. The flame cutting method of high-grade wear-resistant steel is as simple as that of ordinary low-carbon and low-alloy steel. When cutting thick plates of wear-resistant steel, you need to pay attention! !! !! As the thickness and hardness of the steel sheet increase, the tendency of cracks at the cutting edges increases. To prevent the occurrence of cutting cracks in steel plates, the following recommendations should be followed when cutting:

Cutting cracks: Cutting cracks in steel plates are similar to hydrogen-induced cracks during welding. If cracks occur in the cutting edges of steel plates, they will occur within 48 hours to several weeks of cutting thickness. Therefore, cutting cracks are delayed cracks. The larger the thickness and hardness of the steel plate, the larger the occurrence of cutting cracks.

Preheat cutting: The most effective way to prevent steel plate from cracking is to preheat before cutting. Before flame cutting, the steel plate is usually preheated. The preheating temperature depends on the quality grade and thickness of the steel plate. The pre-heating method can be carried out by using a flame burning gun or an electronic heating pad, or it can be heated by a heating furnace. In order to determine the preheating effect of the steel plate, the required temperature should be tested at the heating surface.

Note: Special attention should be paid to the preheating, so that the interface of the steel plate is uniformly heated to avoid local overheating in the area contacting the heat source.

Low speed cutting: Another way to avoid cutting cracks is to reduce the cutting speed. If full-plate preheating is not possible, local preheating can be used instead. The use of low-speed cutting methods to prevent cutting cracks is not as reliable as preheating. It is recommended to preheat the cutting strip with a flame gun several times before cutting, and the preheating temperature should be about 100 ° C.

Special note: The combination of pre-heating and low-speed flame cutting methods can further reduce the occurrence of cutting cracks.

Slow cooling requirements after cutting: Regardless of whether the preheating is not visible for cutting, slow cooling after cutting steel plates will effectively reduce the risk of cutting cracks. If it is stacked after being cut with warm heat, it can be covered with a thermal insulation blanket, which can also realize slow cooling, which requires cooling to room temperature.

Post-cut heating requirements: For cutting of wear-resistant steel plates, heating (low temperature tempering) immediately after cutting is also an effective method and measure to prevent cutting cracks. Cutting thickness of steel plate can be effectively reduced by low-temperature tempering (low-temperature tempering process; moisturizing time: 5min / mm). For the heating method after cutting, the heating method of burning gun, electronic heating blanket and sorrow furnace Heat after cutting.

4. Measures to reduce the softening of steel plate The softening resistance of steel mainly depends on its chemical composition, microstructure and processing method. For thermally cut parts, the smaller the part, the greater the risk of softening the entire part. If the temperature of the steel plate exceeds 200-250 ° C, the hardness of the steel plate will decrease.

Cutting method: When the steel plate is cutting small parts, the heat provided by the welding gun and preheating will be accumulated in the workpiece. The smaller the size of the invisible cutting, the cutting workpiece size must not be less than 200mm, otherwise the workpiece will risk softening. The best way to eliminate the risk of softening is cold cutting, such as water jet cutting. If thermal cutting is necessary, there are limited options for plasma or laser cutting. This is because flame cutting provides more heat to the workpiece and thus increases the temperature of the workpiece.

Underwater cutting method: An effective method to limit and reduce the range of the softening zone. Water is used to cut the steel plate and cutting surface during the cutting process. Therefore, the steel plate can be cut in water, and it can also be sprayed with water on the cutting surface. Use underwater cutting methods to choose between plasma or flame cutting. Underwater cutting has the following characteristics:

Small cutting heat affected zone;

Prevent the hardness of the entire workpiece from decreasing;

Reduce deformation of cutting workpiece;

After cutting, the workpiece can be cooled directly. ^[3]