公开(公告)号：US20180272476A1

公开(公告)日：2018-09-27

申请号：US15762094

申请日：2016-09-23

Applicant: Tianjin University

Inventor： Lianyong XU ,  Yongdian HAN ,  Hongyang JING ,  Lel ZHAO ,  Xiaoqing LV

IPC: B23K35/26 ,  B22F9/04 ,  B22F1/00 ,  B23K35/40 ,  C22C13/00

CPC classification number: B23K35/262 ,  B22F1/0011 ,  B22F9/04 ,  B22F2009/043 ,  B22F2201/11 ,  B22F2201/20 ,  B22F2301/30 ,  B22F2304/10 ,  B22F2998/10 ,  B22F2999/00 ,  B23K35/0244 ,  B23K35/26 ,  B23K35/3601 ,  B23K35/40 ,  C22C13/00 ,  C22C47/14 ,  C22C49/02 ,  C22C49/14 ,  C22C1/05 ,  B22F3/02 ,  B22F3/10

Abstract: This invention discloses a method for preparing a kind of Sn-based silver-graphene lead-free composite solder, including mixing a certain amount of graphene with sodium dodecyl sulfate, then adding a certain amount of dimethylformamide, sonicating for 2 hours, adding a certain amount of silver nitrate to the mixture, continuing the sonication and finally obtaining the homemade. The solders matrix powder is weighed according to different silver-graphene mass fraction required, then poured into a ball-milling tank milling for 5 h. The powder is poured into a stainless steel mold after drying, then placed under hydraulic pressure to 500 Mpa for pressure forming. Later, the cold-pressed cylinder is placed in a high vacuum tube resistance furnace and sintered at 175° C. for 2 hours. After cooling to room temperature, it is formed into a cylinder under the hydraulic press. In this invention, graphene modified with Ag particles is selected as a strengthening material so as to improve the load-transfer between the graphene modified by nano-silver and the Sn matrix, aiming to achieve better strengthening effect.