THE EFFECT OF WIRE PLATING ON THE RELIABILITY OF CRIMPED CONTACTS
TRW SYSTEMS GROUP REDONDO BEACH CA
Pagination or Media Count:
Four groups of specimens were assembled for test in the following manner Group A - Tin plated 26 AWG wire thermally stripped at normal temperature and contact crimped Group B - Tin plated 26 AWG wire mechanically stripped and contact crimped Group C - Tin-plated 26 AWG wire thermally stripped at excessively high temperatures jacket and insulation charred and contact crimped Group D - Silver-plated 26 AWG copper wire 19 strands of 38 AWG thermally stripped at excessively high temperature and contact crimped. Group A, B, C and D contacts were all crimped with the same tool and positioner to limit variables. The silver-plated wire was added to the test because previous test data accumulated by the manufacturer showed no previous contact resistance failures with 26 AWG silver-plated wire. The results showed that all groups met the initial contact resistance requirement of 7 milliohms maximum but the Group D specimens silver-plated wire were the only group to meet the contact resistance requirements after 40 cycles of thermal shock. The Group D specimens had very stable contact resistance and were less than 3 milliohms throughout the test. The other groups had contact resistance values ranging from 10 milliohms to ohms.
- Electrical and Electronic Equipment