| 摘要 |
PROBLEM TO BE SOLVED: To rapidly evaluate the reliability of accelerated life with respect to a solder joint part with high precision by a simple method by estimating the accelerated life after exceeding an inflection point. SOLUTION: The joint evaluation device is equipped with a cooling part 12 and a heating part 13 both of which repeatedly perform heating and cooling with respect to a solder joint part 8, a measuring circuit part 11 and a measuring part 22 both of which measure the resistance value of the solder joint part 8 at a predetermined cycle during hot supply, an arithmetic part 23 for calculating a resistance change ratio and the change speed of the resistance change ratio from the resistance value at each time when the resistance value is measured, a judge part 24 for judging whether the resistance value reaches an inflection point, where the lowering of the change speed of the resistance change ratio is started, from the calculated change speed of the resistance change ratio, an evaluation part 25 for operating the period before the estimate resistance change ratio calculated from the resistance change ratio and the change speed of the resistance change ratio reaches a reference threshold value after reaching the inflection point and an information part 3 for reporting the data of the period obtained from operation. COPYRIGHT: (C)2008,JPO&INPIT |
