The invention provides an austempered
ductile iron adjusting chemical component. The chemical component uses Mn and Si as a base to substitute Mo and Ni, and contains a plurality of elements comprising Cu, B, Nb and Cr to realize low and micro alloying, so the respective effects of all elements are fully performed, the interactive effect promotion is realized, the
hardenability is increased, the
alloy consumption is reduced, and the cost is reduced. The invention also provides a new austempered
ductile iron quenching technology matched with the austempered
ductile iron. The technology is a step
austempering technology using step
quenching oil and an air isothermal furnace. The heat treatment of a workpiece through the technology realizes
crystal grain refinement, good
hardenability, high strength and
toughness, low
hardness (HB190-240) before the step
austempering treatment, and good
processing performances; and the obtained processed austempered ductile iron has a high
hardness (HRC35-56) and extremely less oxidation and deformation, so the precision is guaranteed, and finishing treatments comprising
grinding and the like are not needed. Compared with traditional
nitrate bath
austempering technologies, the austempered ductile iron
quenching technology has the advantages of low cost, no generation of large amounts of harmful substances comprising
nitrite or the like, low
pollution and safety.