For soft tooth surface gear transmission, the hardness of the tooth surface should be selected A: Pinion tooth surface hardnesslarge gear tooth surface hardness B: Pinion tooth surface hardness≤large gear tooth surface hardness
For soft tooth surface gear transmission, the hardness of the tooth surface should be selected A: Pinion tooth surface hardnesslarge gear tooth surface hardness B: Pinion tooth surface hardness≤large gear tooth surface hardness
The hardness of mica is （ ）.
The hardness of mica is （ ）.
武当派的武功以刚为主，刚柔并济。（ ）The martial art of Wudang School emphasizes hardness, and couples hardness with flexibility. （ ）
武当派的武功以刚为主，刚柔并济。（ ）The martial art of Wudang School emphasizes hardness, and couples hardness with flexibility. （ ）
Hardenability和hardness是同一概念。
Hardenability和hardness是同一概念。
There are three common hardness testing methods used in practice, that is, ____, ____ and ____.
There are three common hardness testing methods used in practice, that is, ____, ____ and ____.
Water is characterized by . A: hardness B: flaring up C: downward flowing D: changing
Water is characterized by . A: hardness B: flaring up C: downward flowing D: changing
The hardness, wear resistance and heat resistance of cemented carbide are higher than that of high-speed steel.
The hardness, wear resistance and heat resistance of cemented carbide are higher than that of high-speed steel.
A major objective in designing new ceramics is to overcome A: Hardness B: Brittleness C: Reactivity D: Conductivity
A major objective in designing new ceramics is to overcome A: Hardness B: Brittleness C: Reactivity D: Conductivity
It was essential to ____ science and technology, not just for the economy but for environmental protection as well. A: hard B: harvest C: harness D: hardness
It was essential to ____ science and technology, not just for the economy but for environmental protection as well. A: hard B: harvest C: harness D: hardness
以下选项中表示“硬度”的词汇是_____。 A: hardness B: malleability C: ductility D: density
以下选项中表示“硬度”的词汇是_____。 A: hardness B: malleability C: ductility D: density