... material 38CrMoAL,depth of nitriding 0.5~0.7mm.—Barrel cast aluminum heating,6 zones heating,6 zone cooling2.Die —Type: ... is stainless steel, whole journey vacuum, windows two sides, aluminum lid.—water supply way: concentrated water supply, 4 direction spray4 ... is stainless steel, whole course vacuum ,windows two sides, aluminum lid.—water supply way:concentrated water supply, 4 direction spray