President, Amalgamated Technologies, Inc., Scottsdale, AZ
Pages: 18 Published: Jan 1986
A dynamic test for soldered joints in a coolant environment has been developed that allows definitive coolant comparison with respect to soldered joint response in service. The test unit consists of a heated pressure vessel, capable of handling temperatures up to 149°C and pressures up to 0.21 MPa, and twelve specimen jigs. Soldered joints are made under controlled conditions and exposed in coolant under static and dynamic stress rupture conditions. Joint failure is measured on timers that trip upon specimen fracture.
Solder alloys selected for the program were 70Pb-30Sn, 95Pb-5Sn, and 97Pb-2.5Sn-0.5Ag materials. Four commercially available coolants were tested with the above solders at selected loads. A series of tests was also conducted to examine the effect of water used in diluting the coolant. Different commercial coolant and water combinations were found to produce variable degrees of corrosion and joint failure. Solder bloom was found to increase in engine coolant at radiator operating temperatures in the presence of applied stresses.
solder, coolant, stress-rupture, soldered joint, automotive radiators, solder corrosion, service simulation
Paper ID: STP32979S