详细解释:【化】 硬面; 硬表面; 淬火表面; 表面淬火
英语解释：
动词 hard surface:
cover with asphalt or a similar surface例句：
A small firework consisting of some gravel wrapped in tissue paper with a percussion cap that explodes when thrown against a hard surface.掼炮一种由草纸包住一些砾石制成的小型鞭炮，其打火帽在与坚硬表面撞击时发生 *