| 摘要 |
PURPOSE:To obtain a cam shaft having a uniform assembled size and high accuracy by shrinking a green compact having a specific characteristic by primary sintering and fitting the green compact to a cam shaft then shrinking the same to the final rate by secondary sintering. CONSTITUTION:A part contg. a cam lobe is formed of a green compact which generates a liquid phase and shrinks when sintered. Such green compact molding 13 is primarily sintered at about 1,000-1,120 deg.C to decrease the hole amt. and to shrink the same to the size equiv. to approximately 50% of the final axial shrinkage rate. Such primarily sintered body 15 is fitted and assembled onto a cam shaft 12. The sintered body is secondarily sintered in succession to decrease further the hole amt., by which the secondarily sintered body 16 shrunk to the final shrinkage rate is obtd. Joining of the assembling part to the cam shaft 12 is accomplished by two stages of liquid-phase sintering according to the above- mentioned method and therefore the cam shaft having high joint strength and high accuracy is obtd. |
