固溶炉温均匀性对反重力浇注ZL114A合金力学性能的影响

以反重力浇注的ZL114A合金为研究对象,研究固溶炉温均匀性对合金力学性能的影响。结果表明：在不考虑其它因素条件下,伸长率受到固溶炉温均匀性的影响更显著,硬度及抗拉强度受固溶炉温均匀性影响次之。因此,采用反重力铸造方式生产ZL114A合金时,可以将伸长率降低作为生产异常预警指标,并以伸长率为5.6%作为预警红线。

Nd元素对反重力浇注ZL116合金组织和力学性能的影响

通过OM、XRD、SEM以及室温拉伸试验等方法,开展了Nd元素对反重力浇注ZL116合金显微组织和力学性能的影响研究。结果表明:当Nd元素含量小于0.1%时,随着Nd元素含量的提高,ZL116合金的抗拉强度和伸长率均有所提高。Nd元素主要分布在共晶Si相周围,阻碍共晶Si相的长大,进而可以促进ZL116合金中的长条状共晶Si转化为颗粒状,即:Nd元素对ZL116合金中共晶相具有变质作用,可以促进共晶Si的球化。

铝合金真空吸铸加压凝固技术研究

在自行研制的真空吸铸加压凝固铝合金铸件浇注设备试验的基础上 ,分析了真空吸铸加压凝固的特点 ,针对有代表性的复杂铝合金铸件 ,分析该类铸件浇注系统设计的原理和浇注工艺参数的确定方法 ,研究出

Development of pressure control system in counter gravity casting for large thin-walled A357 aluminum alloy components

Counter gravity casting equipments(CGCE) were widely used to produce large thin-walled A357 aluminum alloy components. To improve the pressure control precision of CGCE to get high quality castings, a pressure control system based on fuzzy-PID hybrid control technology and the digital assembled valve was developed. The actual pressure tracking experiment results show that the special system by applying PID controller and fuzzy controller to varied phases, is not only able to inherit the small error and good static stability of classical PID control, but also has fuzzy control’s advantage of fully adapting itself to the object. The pressure control error is less than 0.3 kPa. By using this pressure control system, large complex thin-walled A357 aluminum alloy castings with high quality was successfully produced.