長(zhǎng)期供應(yīng)LCP VECTRA S625 聯(lián)系電話：18680081166

介紹:

LCP加入高填充劑或合金（PSF/PBT/PA）：

作為集成電路封裝材料、

代替環(huán)氧樹脂作線圈骨架的封裝材料；

作光纖電纜接頭護(hù)套和高強(qiáng)度元件；

代替陶瓷作化工用分離塔中的填充材料。

代替玻璃纖維增強(qiáng)的聚砜等塑料（宇航器外部的面板、汽車外裝的制動(dòng)系統(tǒng)）。

'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.

教你認(rèn)準(zhǔn)注塑缺陷之熔結(jié)痕，對(duì)癥才能下藥！

1.缺陷特征及判定依據(jù)

熔結(jié)痕，也叫熔結(jié)線、熔合線。在大多數(shù)的例子上，熔合線是注塑件的光學(xué)性能和機(jī)械強(qiáng)度較為薄弱的位置。熔合線上可能出現(xiàn)缺口或是變色的現(xiàn)象。缺口特別在深色或光滑透明的注塑件或拋光亮度高的注塑件上更為明顯。變色的現(xiàn)象則在使用金屬色母粒時(shí)特別容易顯現(xiàn)。

2.熔合線案例圖集

3.缺陷形成的原理

當(dāng)兩條或更多的熔流相遇時(shí)，便會(huì)形成熔合線。當(dāng)遇上其他熔流時(shí)，呈弧形的流動(dòng)波峰會(huì)被壓平及與其他熔流黏合在一起。在這過(guò)程中，高黏度的流動(dòng)波峰會(huì)被拉伸。

4.缺陷的可能成因

假如熔解流接合位置的溫度和壓力不夠，熔流前端的邊角位置便出現(xiàn)填充困難。在平滑的表面，可清楚看見(jiàn)沿著熔合線的缺口；而在結(jié)構(gòu)性表面，則會(huì)在熔合線邊緣出現(xiàn)光澤差別。此外，因熔流的接合位置不是單相熔合，所以會(huì)導(dǎo)致脆弱點(diǎn)的形成。如使用含有添加劑（如色母）的塑料，添加劑會(huì)因流向而于熔合線附近整齊排列，導(dǎo)致熔合線附近的顏色偏差更明顯。

5.缺陷排查步驟

為要加強(qiáng)防止熔合線缺口的形成，模壁溫度必須增加至塑料軟化或結(jié)晶溫度的范圍內(nèi)。這樣要將模壁溫度提升30℃以上，從經(jīng)濟(jì)的角度上看來(lái)是不可能的。有規(guī)律的溫度控制容許以經(jīng)濟(jì)效益最佳的方法消減光亮極高的注塑件上的熔合線缺口。使用

獨(dú)立的溫度控制管道，可選擇性地控制熔合線四周的溫度，令熔合線缺口可以完全平合，短暫的加溫可以避免增加模具周邊的溫度，也避免延長(zhǎng)冷卻時(shí)間。但當(dāng)遇上一些結(jié)構(gòu)性平面（色差危區(qū)）的時(shí)候，這種處理方法并非經(jīng)常奏效。要成功應(yīng)用這技術(shù)，取決于附加的溫度控制管道的位置和提升溫度的時(shí)間。對(duì)某非結(jié)晶塑料如ABS、PS、PMMA 和PC 會(huì)達(dá)到特別理想的效果。