孔或焊，通过印刷电路板通常采用小钻头的硬质合金。

Holes, or vias, through a PCB are typically drilled with tiny drill bits made of solid tungsten carbide.

youdao

孔或焊，通过印刷电路板通常采用小钻头的硬质合金。

Holes, or vias, through a PCB are typically drilled with tiny drill bits made of solid tungsten carbide.

youdao