抄録
A fundamental study of iron soldering has been made of the reaction of solid iron with molten tin from the viewpoints of dissolution kinetics and metallography. Small iron cylinders were immersed in molten tin in the temperature range from 445 to 780°C for 10 to 160 min under a static condition utilizing the soldering flux. The obtained values of initial dissolution-rate constant of solid Fe into molten Sn are 3.37×10−4∼1.12×10−3 cm/sec and the activation energy for dissolution depends on the temperature. Owing to the formation of intermetallic compound in solid-liquid interface, the dissolution behaviour in the high-temperature range above 496°C differs from that in the low-temperature range below 496°C. The intermetallic compound formation does not appear to act as a dissolution barrier. In the high-temperature range, the dissolution process is controlled by diffusion in the boundary layer of molten metal. In the low-temperature range, the process is controlled by the formation of an intermetallic compound at the early reaction time, but a transition of reaction control of the alloy layer and molten metal occurs with time. The dissolution of solid iron into molten tin proceeds with an intensive reaction between molten tin and the alloy layer in relatively rapid growth.
