EKH-SS系列机械加工说明
1. Cutting tool Since Krefine PEEK ESD grades are filled with carbon materials, tool abrasion should be taken into consideration. Abrasion resistant steel is desirable for tool, hard metal must be used. High speed Titanium coating is recommended. 2. Drilling Revolution speed is one of the most important factors for drilling. Suitable revolution speed can give high precision machining without flash. The normal revolution speed is from 5000 tó 10000 r.p.m and the drill movement speed is about from 50 to 150mm/min. 3. Cutting speed When machining Krefine PEEK ESD grades, the cutting speed should be lowered (200mm/min). 4.Example of drilling Table 1 shows the example of drilling conditions for 0.56mm hole diameter and 0.8mm between center ofholes applicable to Krefine PEEK ESD grade, EKH-SS11. Figure 1 shows picture after drilling.
什么是发光二极管(Light Emitting Diode,简称LED)
是一种藉外加电压激发电子而放射出光(电能→光)的光电半导体组件。发光现象属半导体中的直接发光(没有第三质点的介入)。整个发光现象可分为三个过程(直接发光): 价电带的电子受外来的能量(顺向偏压),被激发至导电带,并同时于价电带遗留一个电洞,形成电子-电洞对。 受激发的电子于导电带中,与其它质点碰撞(散射),损失部份能量,而接近导电带边缘。 一旦导电带边缘的电子于价电带觅得电洞时,电子即从导电带边缘,经由陷阱中心(释放热能)或发光中心(释放光能),回到价电带与电洞复合,电子-电洞对消失。 因为LED主要是电子经由发光中心与电洞复合而发光,所以是一种微细的固态光源,不但体积小、寿命长、驱动电压低、反应速率快、耐震性特佳,而且能够配合轻、薄和小型化之应用设备的需求,成为日常生活中十分普遍的产品。 利用各种化合物半导体材料及组件结构之变化,设计出不同的LED。依其发光波长分为可见光、不可见光(红外光、紫外光)。