硬度5H什么意思
硬度5H什么意思
化学人气:186 ℃时间:2020-02-05 22:34:55
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估计指铅笔的硬度.铅笔硬度等级6B 5B 4B 3B 2B B HB F H 2H 3H 4H 5H 6H 7H 8H 9H从软到硬,根据wolff-Wilborn硬度规范,是由软到硬的顺序测试,第一支会留下刮痕的铅笔,视为最终的“Wolff-wilborn铅笔硬度”,三菱硬度...
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