Material name: gray iron 200
Standard: GB/T 9439-2010
Refers to gray cast iron with a minimum tensile strength of 200MPa.
Chemical composition: C:3.0 ~ 3.6s :≤0.12 P: <0.15 Mn: 0.6 ~ 1.0 Si: 1.4 ~ 2.0
Scope of application
Low tensile strength and plasticity, good casting performance and damping performance, mainly used for casting automobile engine cylinders, cylinder jackets, lathe beds and other pressure and vibration components.
If the technical conditions of the demander include acceptance requirements for chemical components, the requirements of the demander shall apply. The frequency and quantity of the chemical composition shall be determined by the supplier or by the supplier.
If the chemical composition is not required by the buyer, the chemical composition shall be determined by the supplier, and shall not be used as the basis for acceptance of the casting. However, the selection of chemical composition must ensure that the casting materials meet the requirements of mechanical properties and microstructure specified in this standard.
Spectral chemical analysis shall be performed in accordance with GB/T 4336.
Conventional chemical composition analysis of castings shall be performed in accordance with GB/T 223.3, GB/T 223.4 and GB/T 223.60.
1. Important castings in general machinery manufacturing, such as cylinders, gears, frames, beds and surfaces of metal cutting machines; Etc.
2. Cylinder blocks, cylinder heads, pistons, brake wheels, coupling discs and piston rings for gasoline and diesel engines of automobiles and tractors
3. It has the joint construction of measuring planes, such as: marking plates, v-shaped irons, flat rulers, horizontal instrument frames, etc
4. Hydraulic cylinders, pump bodies, valve bodies under medium pressure of 7.85mpa and pump shells and containers requiring certain corrosion resistance, such as pump bodies, pump covers, impellers, etc. of submersible sewage pumps
5. Circumferential velocity > 12 ~ 20 m/s pulley and other listed items conform to the conditions of the parts
6. Parts to be surface-hardened
Cast iron level
High strength cast iron, pearlitic base, good strength, abrasion resistant, heat resistance and vibration reduction. The casting performance is good, and manual aging treatment is needed.
The working conditions
1. Parts under greater stress (bending stress <29.40MPa)
2. Pressure per unit area between friction surfaces > 0.49mpa (pressure > 1.47mpa for large castings working under wear and tear greater than 10t)
3. Certain air tightness or a weak corrosion resistance medium is required