Chromium (Cr)

Chromium (Cr)
Chromium can increase its quench-hardening ability and steel second sclerosis role. Can improve the hardness of high carbon steel and abrasion resistance and not make steel become fragile; Content of more than 12%. Make steel has good oxidation stability and resistance to oxidation corrosion of the role of the media. Also increase steel heat strong sex, chromium for stainless steel and heat resistant steel acid of the main alloy element.

Chromium can improve carbon steel rolling strength and hardness of the state. Reduce the elongation and area reduction. When chrome content of more than 15%, strength and hardness down under, elongation and area reduction is correspondingly improved. Including the chrome by grinding easy to obtain higher parts of the surface processing quality.

Chromium in conditioning the main function is to improve steel its quench-hardening ability. Make the after tempering steel quenching has good comprehensive mechanical performance, in carburizing steels can be formed in cr-containing carbon, so as to improve the material surface wear resistance.
Contain chromium spring steel in the heat treatment to the decarburization. Chromium can improve the wear resistance of the steel/" target="_blank" class="keylink">tool steel, hardness and red rigid. Good temper stability. In electrothermal alloy, chromium alloy can improve the oxidation resistance, resistance and strength.
(1) for the organization and show do steel heat treatment effect
A, chromium and iron to form A continuous interstitial, narrow the austenitic phase area of the city. Chromium and carbon form a variety of carbon, and the affinity of carbon than iron and manganese and lower than tungsten, molybdenum, etc. Chrome and iron can form intermetallic σ phase (FeCr)
B, chrome make pearlite of carbon in concentration and austenitic carbon limit solubility reduced
C, slow austenite decomposition rate, improve its quench-hardening ability of steel. But also increase steel brittleness of tendency
(2) for the role of the mechanical properties of the steel
A, improve the strength and hardness of the steel. Add other alloying elements, the effect is remarkable
B, improve brittle transition temperature of steel
C, in the amount of containing Cr high Fe-Cr alloy, if a σ separating, impact toughness fell sharply
(3) of steel of physical, chemical and process performance role
A, improve the wear resistance of the steel, the grinding, easy to get A higher surface finish
B, reduce the steel of electrical conductivity, reduce the temperature coefficient of resistance
C, improve the coercive force and surplus steel magnetic feeling. It is widely used for manufacturing and magnets
D, chromium to the surface of steel passivation membrane formation, when a certain content of the inscription, improve the steel corrosion resistance (especially nitric acid). If there is a chromium carbides exhalation, make steel corrosion resistance of decline
E, improving steel antioxidant properties
F, chrome easy form dentrites segregation, reduce steel plastic deformation
G, due to the chrome steel thermal conductivity rate, when the hot working slowly warming, forging, rolled to slow cold
(4) in the application of steel
A, the main use of chromium steel/" target="_blank" class="keylink">alloy steel and improve its quench-hardening ability, and can be in carburizing surface formation including chromium carbides in order to improve abrasion resistance
B, spring steel of chromium and alloy elements were he to provide the comprehensive performance
C, bearing steel in the main use of chrome carbide special to the wear resistance of contribution after grinding and sell the advantages of studying and high degree
D, steel/" target="_blank" class="keylink">tool steel and high speed steel paper mainly use chrome improve abrasion resistance, and the effect of has certain tempering stability and toughness
E, stainless steel, heat-resistant steels chromium manganese, nitrogen, often with nickel etc joint then use, when need to form the austenitic steel, stability of chromium and stability ferrite austenitic manganese, nickel must have certain proportion between, such as Cr18Ni9, etc
F, fewer resources in chrome. Should save as far as possible the use of chrome