| 摘要 |
The present invention relates to an aluminum push rod producing method comprising: (S10) a blank producing step of producing a cylindrical aluminum blank (B); (S20) a softening heat treatment step of softening the blank (B) to have a hardness of 25-40 HB by annealing heat treatment (T_0) of the blank (B); (S30) a blank film step of film treating the softening heat treated blank (B) with a film treatment (C) including phosphate; (S40) a forging molding step of closing a floor part (15) of the blank (B) passing through the blank film step (30), forming a hollow part (11) in a middle thereof, and molding a long hollow cylindrical push rod molding body (S) of which an inner circumferential face has a plurality of uneven spline members (13) formed in a long shape thereon using a forging mold (100) including an upper punch part (110) and a lower die part (120); and (S50) a hardening heat treatment step of hardening a heat treating push rod molding molding body (S) passing through the forging molding step (S40) to be hardened at 80-100 HB. |
