Surface roughness of hardened zone of the ball head pin has been improved on by the use of inert gas …

在感应加热过程中采用惰性气体和改进的工装夹具改善了淬火区的表面粗糙度。

youdao

The items he creates are so small that most of them fit on the head of a pin.

他创造的东西非常小，大多数都可以放在针尖上。

youdao

Medieval scholastics are reputed to have enjoyed debating how many angels you can fit on the head of a pin.

中世纪的哲学家们十分热衷于讨论这么一个问题，那就是一根针头上可以容纳多少个天使一起跳舞。

youdao

"I was trying," he said, "to put the history of mankind in one sentence." Later he said, "I am still trying to do it, but now I want to put it all on the head of a pin."

VOA: special.2010.01.03

We are in the realm, here, of angels dancing on the head of a pin.

BBC: Global warming: Andrew Pendleton and James Delingpole

Nine hundred million of these zinc oxide crystals could be spread across the head of a pin in a single layer.

FORBES: The Science of Small

Some 900 million of these zinc oxide crystals can fit in a single layer on the head of a pin.

FORBES: The science of small