感應加熱技術具有高效率、乾淨和控制精確性等優點，因此成為許多工程應用首選的加熱技術。近一世紀，家用電器的普及化以及近年來電動車的興起，使得馬達之核心零件－鐵芯的製程良率顯得相當重視。自黏式鐵芯成為目前製程上的重要技術，其將電磁鋼片疊層後置於環型激磁線圈內加熱，軟化電磁鋼片表面的環氧樹脂膠製成鐵芯。
鐵芯製程時，周圍必須透過治具定位疊層狀的電磁鋼片。然而，加熱過程中之治具與鐵芯間會因為加熱功率、熱傳遞所引起的溫度分佈及邊界約束條件，導致其產生熱應力而存在變形的可能性。因此，本研究利用有限元素法之數值模擬分析鐵芯在加熱過程的熱應力分佈。為了減少真實分層鐵芯幾何外型以及電磁-熱-力耦合所造成的計算成本，因此將材料參數簡化為複合層等效參數。除此之外，將電磁-熱計算所得到的集膚表面熱源，以等效邊界熱源的形式進行熱-力耦合之熱應力分析。熱應力分析方面，針對使用不同陶瓷材料作為治具對於加熱鐵芯時的熱應力進行比較。最後，針對鐵芯與治具間存在公差配合關係時，其熱應力影響進行分析。
分析結果表明，加熱至目標溫度的環境下，治具外徑受到約束會導致鐵芯之熱應力超過降伏強度而在降溫後存在殘留應力。治具外徑不受約束時，鐵芯熱應力不超過降伏強度，而選用陶瓷治具造成鐵芯熱應力由大到小分別為氮化矽、氧化鋯及氧化鋁。且當加熱功率越大，鐵芯的熱應力數值越大。更細微比較可知，氧化鋯與鐵芯接觸面的徑向應力增加較明顯，氧化鋁及氮化矽的徑向應力則無明顯變化。

The process of motor core manufacturing has been crucial for acquiring higher efficiency since the demand of electrical car grows rapidly. And the backlack-coated electrical steel for adhesive-bonded electrical steel cores (glued iron core) by heating jig is one of the process. It can obtain lower iron loss and higher dynamic stability during motor operation. However, jig can produce extra thermal stress and arbitrary deformation during heating process. Therefore, this study performe a method of using the numerical simulation of the finite element to analyze the thermal stress distribution of the iron core during the heating process.
The analysis results show the stress distribution during heating (induction heating) to the target temperature by different situations such as like the outside jig is constrained, which will cause the thermal stress of the iron core to exceed the yield strength and there will be residual stress after cooling. When the outside jig is not restricted, the thermal stress of the iron core does not exceed the yield strength, and the thermal stress of the iron core caused by the selection of ceramic jigs is silicon nitride, zirconia or aluminum oxide. And when the heating power is larger, the thermal stress of the iron core is larger. A more detailed comparison shows that the radial stress of the contact surface between zirconia and the iron core increases significantly, while the radial stress of alumina and silicon nitride does not change significantly.

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