US 12,338,511 B2
Aluminum alloy diecast, diecast unit and method for producing same
Shunzo Aoyama, Toyohashi (JP); Kazuki Sasaki, Toyohashi (JP); and Yoshiteru Kondo, Toyohashi (JP)
Assigned to AHRESTY CORPORATION, Toyohashi (JP)
Appl. No. 17/765,062
Filed by Ahresty Corporation, Toyohashi (JP)
PCT Filed Oct. 1, 2019, PCT No. PCT/JP2019/038761
§ 371(c)(1), (2) Date Mar. 30, 2022,
PCT Pub. No. WO2021/064865, PCT Pub. Date Apr. 8, 2021.
Prior Publication US 2022/0341005 A1, Oct. 27, 2022
Int. Cl. C22C 21/02 (2006.01); C22C 21/08 (2006.01); C22C 22/00 (2006.01); C22F 1/043 (2006.01); C22F 1/047 (2006.01)
CPC C22C 21/08 (2013.01) [C22C 21/02 (2013.01); C22C 22/00 (2013.01); C22F 1/043 (2013.01); C22F 1/047 (2013.01)] 8 Claims
 
1. An aluminum alloy diecast made of an aluminum alloy comprising 7.5% to 11.5% of Si, 0.1% to 0.6% of Mg, 0.2% to 0.9% of Mn, 0.2% or less of Ti and 0.1% or less of Sr in a mass ratio and a remainder made of Al and inevitable impurities, the aluminum alloy diecast comprising:
a part to be press-fitted having a press-fitted front surface onto which a joining member is press-fitted and a press-fitted back surface located at an opposition side of the press-fitted front surface; and
a main body part having a main body front surface connected to an edge of the press-fitted front surface and a main body back surface connected to an edge of the press-fitted back surface and integrally formed with the part to be press-fitted, wherein
an average hardness of the part to be press-fitted obtained by averaging Rockwell hardness HRF of the press-fitted back surface is lower than an average hardness of the main body part obtained by averaging Rockwell hardness HRF of the main body front surface or the main body back surface, and wherein
the press-fitted front surface or the press-fitted back surface comprises a melted part having a different crystal structure relative to surrounding portion.