What Is Chrome Steel?

Chrome steel refers to chromium-containing alloy steel, which is hard, wear-resistant, corrosion-resistant, and does not rust. It can be used to make machines and tools. Has high oxidation resistance and corrosion resistance. For different environments, other elements such as molybdenum, vanadium, tungsten, titanium, niobium, and boron are often added.

Low carbon chromium steel can be measured with Brinell hardness tester or Rockwell hardness tester B scale.

The annealed and tempered medium carbon chromium steel can be measured with a Brinell hardness tester or a Rockwell hardness tester B or C scale.

The hardened medium carbon chromium steel can be measured with a Rockwell hardness tester C scale.

High carbon chromium steel can be measured with Rockwell hardness tester C scale.

Surface carburizing and nitriding chromium steels should be measured with a surface Rockwell or Vickers hardness tester.

For large parts, you can also use a Shore hardness tester, simple

Parts that work under the conditions of slurry erosion and corrosion conditions, such as slurry pumps and pipelines, must be resistant to the erosion and abrasion of solid particles in the slurry. Therefore, this material This dual effect can lead to the rapid failure of these components. Medium chromium steel (Cr4-6%) is a wear-resistant material used to manufacture parts and components under this working condition. The common form of failure of such parts made of medium chromium steel during use is local severe wear. In addition, there will be local wear and tear resulting in slurry leakage. How to improve the service life of such parts and reduce the cost of use is a problem that materials workers need to solve. Relevant research shows that pre-protection and repair of wear failure sites is one of the effective and economical ways to solve this problem, and this method has been paid more and more attention by people.

In order to reasonably select the surfacing materials for the repair of the medium chromium steel wearable parts according to the working conditions, it is necessary to systematically study the slurry erosion corrosion and wear behavior of different surfacing layers under different working conditions ^[1]

The use of high-chromium casting rolls of high-chromium iron and high-chrome steel casting rolls is a major innovation in roll manufacturing technology in recent years following the use of composite casting of high-alloy infinitely cold-hardened cast iron rolls and semi-steel rolls. New material high-chromium steel composite casting rolls are replacing ultra-high carbon cast steel rolls, needle-shaped ductile iron rolls, and composite cast infinite cold-hard cast iron rolls.

Due to the relatively high carbon content and alloying element content in high carbon and high chromium steels, the matrix microstructure contains a larger amount of eutectic carbides, which has better high temperature wear resistance than alloy semi-steel rolls. The carbon content is lower than that of high-chromium cast iron, and it has certain mechanical strength. It has gradually replaced high-chromium cast iron rolls and alloy semi-steel rolls. High-carbon high-chromium steels are widely used as finishing work rolls, wide and medium-thick plates. Rolling and finishing work rolls, roughing work rolls for continuous rolling mills for hot-rolled strips, finishing rolls for bar mills and work rolls for small sections.

Although the application of high-carbon high-chromium steel rolls is becoming more and more widespread, the outer layer of high-carbon high-chromium steel rolls is easy to segregate. During the cooling and solidification process, the working layer of high-carbon high-chrome steel composite rolls is liable to form coarse network carbides. This network structure weakens the continuity of the high-carbon high-chromium steel matrix, reduces the impact toughness of the roll, and is not conducive to the improvement of the comprehensive mechanical properties of the roll. Due to the cyclic alternating thermal stress in the production process, the thermal fatigue cracks of the rolls will appear. The harsh network carbides provide a way for the microcracks to propagate, which in turn will cause the roll surface to peel and even the roll body to break, resulting in The rolls cannot meet the requirements for use, which limits the application and promotion of high carbon high chromium steel composite casting rolls ^[3] .