菜单
  
    Abstract Cooling system of an injection mold is important for the promotion of production rate and the quality of injection plastic components. Conformal cooling channels are newly developed temperature-adjusting method to promote the efficiency of cooling system. They can be made in the injection mold inserts via the method of indirect selective laser sintering combined with traditional powder metallurgy. This work discussed some processes such as thermal transmission, powders removing, and metal melt infiltration during the manufacturing of the mold inserts in detail. The result showed that redundant powders outside of laser-scanned areas might be sintered together with the sintered parts owing to the accumulation of laser energy during sintering process. This was solved by switching the temperature to initial level after one layer had been sintered.A limit length corresponding to some certain power vacuum system was found when the removal of unsintered powders in the cooling channels was carried out. Therefore, some subsidiary channels leading the cooling channels outside were made to help the removal of powders within the cooling channels. Dripping method was adopted during metal melt 22872
    infiltration process, which was proven to be relevant for
    maintaining of the final shape of infiltrated inserts.
    Keywords Selective laser sintering . Injection mold .
    Conformal cooling channels .Manufacturing detail
    1 Introduction
    The production rate and the quality are much of a concern
    currently when more and more plastic components with
    complex structures are demanded. The adjusting of cooling
    rate and thermal arrangement through conformal cooling
    channels (CCC) provide an effective way to satisfy these two
    requirements. Nowadays, rapid manufacturing methods
    offer the opportunity to create CCC in the core/cavity inserts
    of injection mold. Among these methods, selective laser
    sintering (SLS) is the appropriate one. Metal powders
    blended with polymer material are heated by laser beam
    layer by layer to generate a green shape with CCC firstly.
    Then, the polymer material is burnt out when the green shape
    is heated up to degradation point of the polymer material,
    and it is presintered with the increasing of temperature from
    the degradation point. Finally, the presintered shape with
    metal material (infiltration metal) of low melting point is
    heated at a higher temperature than the melting point of the
    infiltration metal to finish the infiltration densification.
    Although several previous works have discussed the
    manufacturing of injection mold insert with CCC by using
    indirect SLS, they focused only on the surface treatment
    method of SLS green insert [1], the thermal properties of
    SLS hybrid materials and the optimization of cycle time
    of the mold [2], and the CCC arrangement for the purpose
    of achieving the temperature homogeneity within the insert
    [3]. However, the manufacture cycles of CCC inserts werenot mentioned in these investigations. Lakshminarayan et al.
    [4] indicated in 1995 that iron–copper composite part can be
    produced via indirect SLS combined with traditional powder
    metallurgy method employed in injection tooling. But they
    only discussed the mechanical properties of the copper
    infiltrated iron parts and their application performance.
    Ikonen and his coworkers in 1997 studied the manufacturing
    of injection mold through indirect SLS, but they also briefly
    presented the several cycles such as sintering, debinding,
    and infiltration processes [5]. Similar with Lakshminarayan,
    they employed polymer-coated metal powders as forming
    materials and did not discuss the key points of these
    processing cycles. For an example, the thermal transmission
    between the powders, air, and scanning layers during laser
    sintering, and its controlling were not found in their works.
  1. 上一篇:建筑木材的安全性英文文献和中文翻译
  2. 下一篇:动觉触觉交互学习系统英文文献和中文翻译
  1. 汽车内燃机连杆载荷和应...

  2. 审计的优化管理英文文献和中文翻译

  3. FPGA的全景拼接相机的优化...

  4. 气味源定位的有限时间粒...

  5. PLC仿真的虚拟工厂英文文献和中文翻译

  6. ZigBee-RFID混合网络的节电英文文献和中文翻译

  7. PLC可编程控制器的介绍英文文献和中文翻译

  8. 上市公司股权结构对经营绩效的影响研究

  9. C++最短路径算法研究和程序设计

  10. NFC协议物理层的软件实现+文献综述

  11. g-C3N4光催化剂的制备和光催化性能研究

  12. 现代简约美式风格在室内家装中的运用

  13. 中国传统元素在游戏角色...

  14. 高警觉工作人群的元情绪...

  15. 江苏省某高中学生体质现状的调查研究

  16. 巴金《激流三部曲》高觉新的悲剧命运

  17. 浅析中国古代宗法制度

  

About

优尔论文网手机版...

主页:http://www.youerw.com

关闭返回