Gray Cast Iron Investment Casting
Gray cast iron castings are usually produced by sand casting process, however, for some castings which require precision accuracy and have complex structure, the investment casting process is also a good choice.
When we cast the gray iron, we strictly follow the chemical composition and mechanical properties according to the stardards or requirements from the customers. Besides, we have the ability and equipment to test if there is casting defects inside the gray iron sand castings.
Though cast irons can have a carbon percentage between 2 to 6.67, the practical limit is normally between 2 and 4%. These are important mainly because of their excellent casting qualities. Gray iron is cheaper than ductile iron, but it has much lower tensile strength and ductility than ductile iron. Gray iron can not replace the carbon steel, while the ductile iron could replace the carbon steel in some situation due the high tensile strength, yield strength and elongation of ductile iron.
Investment (lost wax) casting is a method of precision casting complex near-net-shape details using replication of wax patterns. Investment casting or lost wax is a metal casting process that typically uses a wax pattern surrounded by a ceramic shell to make a ceramic mold. When the shell dries, the wax is melted away, leaving only the mold. Then the casting component is formed by pouring molten metal into the ceramic mold.
Silica sol casting process is the main investment casting process of RMC investment casting foundry. We have been developing new technology of adhesive material to achieve much more economical and effective adhesive material to build the slurry shell. It is a overwhelming trend that Silica sol casting process replaces the rough inferior water glass process, especially for stainless steel casting and alloy steel casting. Besides the innovated molding material, the silica sol casting process has also being innovated to much steadier and less heat expanding.
|Item according to DIN EN 1561||Measure||Unit||EN-GJL-150||EN-GJL-200||EN-GJL-250||EN-GJL-300||EN-GJL-350|
|EN-JL 1020||EN-JL 1030||EN-JL 1040||EN-JL 1050||EN-JL 1060|
|0.1% Yield Strength||Rp0,1||MPA||98-165||130-195||165-228||195-260||228-285|
|Elongation Strength||A||%||0,3 – 0,8||0,3 – 0,8||0,3 – 0,8||0,3 – 0,8||0,3 – 0,8|
|0,1% Compressive Strength||σd0,1||MPa||195||260||325||390||455|
|Modules of elasticity||E||GPa||78 – 103||88 – 113||103 – 118||108 – 137||123 – 143|
|Brinell hardness||HB||160 – 190||180 – 220||190 – 230||200 – 240||210 – 250|
|Tension and pressure change||σzdW||MPa||40||50||60||75||85|