PURPOSE: To eliminate the abrasion of a die, the seizure of die and a panel, or a galling flaw of the panel that occur particularly during press working by melt spraying a powder material for melt spraying of a specific composition thereby forming a melt sprayed layer of high resistances to abrasion galling.
CONSTITUTION: A powder material consisting of ≥40 Ni, 3W8 Si, 0.1W0.5 B, 0.3W2 Nb, 0.2W1.5 C by wt%, and the balance Fe and unavoidable impurities are melt sprayed. Here, the Ni prevents seizure and galling phenomena, and requires the above-mentioned amount. The Si increases hardness, and below the lower limit, there is virtually no effect and abrasion resistance is insufficient. Above the upper limit, the abrasion resistance does not increase markebly, and conversely, it shows a tendency toward degradation of galling resistance. The B increases hardness and improves abrasion resistance and the effect thereof is much higher in the presence of the C, but above the upper limit, it leads to cracking of the melt sprayed layer and degradation in machineability after melt spraying. The Nb lowers crack sensitivity and improves abrasion resistance, but above the upper limit, it lowers galling resistance. The C improves abrasion resistance but above the upper limit, it flows the panels.
KISHIDA KATSUHIRO
MAKUCHI YUTAKA
HIRAO SUMIO
