详细介绍:
长期供应LCP VECTRA E830iPd
介绍:
LCP加入高填充剂或合金(PSF/PBT/PA):
作为集成电路封装材料、
代替环氧树脂作线圈骨架的封装材料;
作光纤电缆接头护套和高强度元件;
代替陶瓷作化工用分离塔中的填充材料。
代替玻璃纤维增强的聚砜等塑料(宇航器外部的面板、汽车外装的制动系统)。
'A way of letting me know if Snape's giving you a hard time. No, don't open it in here!' said Sirius, with a wary look at Mrs Weasley, who was trying to persuade the twins to wear hand-knitted mittens. 'I doubt Molly would approve - but I want you to use it if you need me, all right'
'OK,' said Harry, stowing the package away in the inside pocket of his jacket, but he knew he would never use whatever it was. It would not be he, Harry, who lured Sirius from his place of safety, no matter how foully Snape treated him in their forthcoming Occlumency classes.
'Let's go, then,' said Sirius, clapping Harry on the shoulder and smiling grimly, and before Harry could say anything else, they were heading upstairs, stopping before the heavily chained and bolted front door, surrounded by Weasleys.
'Goodbye, Harry, take care,' said Mrs Weasley, hugging him.
'See you, Harry, and keep an eye out for snakes for me!' said Mr Weasley genially, shaking his hand.
'Right - yeah,' said Harry distractedly; it was his last chance to tell Sirius to be careful; he turned, looked into his godfathers face and opened his mouth to speak, but before he could do so Sirius was giving him a brief, one-armed hug, and saying gruffly, 'Look after yourself, Harry.' Next moment, Harry found himself being shunted out into the icy winter air, with Tonks (today heavily disguised as a tall, tweedy woman with iron-grey hair) chivvying him down the steps.
教你认准注塑缺陷之熔结痕,对症才能下药!
1.缺陷特征及判定依据
熔结痕,也叫熔结线、熔合线。在大多数的例子上,熔合线是注塑件的光学性能和机械强度较为薄弱的位置。熔合线上可能出现缺口或是变色的现象。缺口特别在深色或光滑透明的注塑件或抛光亮度高的注塑件上更为明显。变色的现象则在使用金属色母粒时特别容易显现。
2.熔合线案例图集
3.缺陷形成的原理
当两条或更多的熔流相遇时,便会形成熔合线。当遇上其他熔流时,呈弧形的流动波峰会被压平及与其他熔流黏合在一起。在这过程中,高黏度的流动波峰会被拉伸。
4.缺陷的可能成因
假如熔解流接合位置的温度和压力不够,熔流前端的边角位置便出现填充困难。在平滑的表面,可清楚看见沿着熔合线的缺口;而在结构性表面,则会在熔合线边缘出现光泽差别。此外,因熔流的接合位置不是单相熔合,所以会导致脆弱点的形成。如使用含有添加剂(如色母)的塑料,添加剂会因流向而于熔合线附近整齐排列,导致熔合线附近的颜色偏差更明显。
5.缺陷排查步骤
为要加强防止熔合线缺口的形成,模壁温度必须增加至塑料软化或结晶温度的范围内。这样要将模壁温度提升30℃以上,从经济的角度上看来是不可能的。有规律的温度控制容许以经济效益最佳的方法消减光亮极高的注塑件上的熔合线缺口。使用
独立的温度控制管道,可选择性地控制熔合线四周的温度,令熔合线缺口可以完全平合,短暂的加温可以避免增加模具周边的温度,也避免延长冷却时间。但当遇上一些结构性平面(色差危区)的时候,这种处理方法并非经常奏效。要成功应用这技术,取决于附加的温度控制管道的位置和提升温度的时间。对某非结晶塑料如ABS、PS、PMMA 和PC 会达到特别理想的效果。
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