ตัวกรองผลการค้นหา
diamond of the first water
แปลว่าเพชรน้ำหนึ่ง
A Diamond In The Rough
Brale
แปลว่า(english) A diamond penetrator, conical in shape, used with a Rockwell hardness tester for hard metals.
Boron (chemical symbol B)
แปลว่า(english) Element N. 5 of the periodic system. Atomic weight 10.82. It is gray in color, ignites at about 1112 (degrees) F. and burns with a brilliant green flame, but its melting point in a non-oxidizing atmosphere is about 4000 (degrees) F. Boron is used in steel in minute quantities for one purpose only- to increase the hardenability as in case hardening and to increase strength and hardness penetration.