The electromagnet coil former was analyzed by means of metallurgical microscope. The results shows that cracks results from excessive high temperature while casting and material embrittlement.

用金相显微镜对衔铁线圈骨架的裂纹进行分析。结果表明，由于锻造加热温度偏高， 材料脆化导致裂纹形成。

youdao

The MF voice coil is of copper-coated aluminium ribbon, expensively edge-wound over a polyimide former to increase sensitivity by maximising the amount of copper in the magnet gap.

中频音圈为镀铜铝带，在其聚酰亚胺成形品上有昂贵的饰边，尽可能加大铜在磁隙中的量来增加灵敏度。

youdao