注射成型烧结永磁铁氧体辐射环的制备及脱脂工艺研究

应用粉末注射成型(PIM)烧结技术制备了锶铁氧体辐射环,并对其微观组织、磁性能、脱脂及烧结工艺进行了研究.结果表明,粉末注射成型样品采用溶剂脱脂、热脱脂和烧结工艺处理后,得到的辐向取向永磁环脆性降低,开裂明显减少,环形保持良好.其密度达到4.89 g/cm3,磁性能参量如下:剩余磁感应强度Br为0.398 T,内禀矫顽力Hcj为236.8 kA/m,最大磁能积(BH)max为29.2 kJ/m3,该磁性能水平与传统粉末冶金磁体的磁性能相当,将注射成型烧结技术应用于永磁铁氧体的制备具有很好的应用前景.     

Study on ceramic photonic bandgap structure with three-dimensional diamond lattice

A novel process, which was based on powder injection molding, was investigated for the fabrication of ceramic photonic bandgap structure with three-dimensional diamond lattice. The SiO2-TiO2 ceramic powder was mixed with a water-soluble agent to produce slurry. The slurry was then injected into an epoxy mold with inverse diamond lattice, fabricated by the stereolitographic rapid prototyping process. To increase the density of the green compact, cold isostatic pressing was applied on the unit. Using thermal debinding, the water-soluble agent and the epoxy were extracted at 360 and 650 K, respectively. Sintering was immediately done at 950 K for 5 h and the desired three-dimensional ceramic structure was obtained. The calculated band diagram for this structure indicated the existence of an absolute photonic bandgap for all wave vectors. At 14.7-18.5 GHz, a complete band gap was located with a maximum attenuation of 30 dB at 17 GHz, when transmission was measured in the 〈100〉 direction between 10 and 20 GHz.     

Sintering products molded by injecting ceramic and metal powders

The injection molding products with different volume ratios of ZrO2 ceramic powder to 316L stainless steel powder were prepared. Properties and structure of the products were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM) and transmission electron microscope (TEM). The results show that the compressive stress exists in the products and the bend strength reaches 300 MPa. ZrO2 phase and stainless steel phase are uniform in samples. The toughness of ceramic increases with the increasing the content of stainless steel. Through TEM study of the interface, some crystalline orientation relationships are determined.     

HK40钢的渗铝新工艺及抗碳化腐蚀性能研究

采用金相显微镜(OM)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线能谱分析仪(EDAX)等仪器设备研究了HK40钢的渗铝及其抗碳化腐蚀能力.试验结果表明,通过调整渗剂中特种添加剂与铝粉的比例和渗铝温度等工艺参数,可达到控制渗铝层相组成的目的.与传统一段法固体粉末渗铝工艺相比,两段法固体粉末渗铝工艺可提高渗速约60%.HK40钢的渗铝层由NiAl相和Ni3Al相组成时,其抗碳化腐蚀能力得到明显提高.     

抚顺石化公司270kt/a石蜡成型装置成型机开汽成功

2012年2月13日,抚顺石化公司270kt/a石蜡成型装置A、B2套成型机分别于2时18分、6时20分实现开汽成功。已生产出合格板蜡产品。成型装置A、B2套成型机及配套系统在2011年建成开工后,发现氨管线内环氧粉未树脂防涂层严重脱落,将氨线堵堵     

高强度粉未冶金铜-铁双金属替代全铜构件在机械设备上的应用

全铜机械构件的制造，历来都是根据其使用性能的要求，以铜或铜的合金为材料铸造成坯后，经机械加工制造而成。因此，铜的消耗多，加工效率低，生产成本高，一直是机械制造行业未能很好解决的问题。高强度粉末冶金铜——铁双金属替代全铜构件在机械设备上应用成功，为解决这一技术难题有了突破性的进展。     

RPC的增强机理及其在桥梁工程中的应用

介绍了活性粉末混凝土（RPC）的力学性能与增强机理，阐述了国内外活性粉末混凝土在桥梁工程中的应用，并分析了它在桥梁应用中的发展潜力及其应用前景。     

载粉末活性炭过滤处理微污染原水的试验研究

载粉末活性炭(PAC)过滤集PAC吸附与过滤于一体,能够应用于微污染原水处理。配水试验结果表明:粒径为1.25-2.5mm,厚度为1000mm的聚苯乙烯滤料层能够用于载PAC过滤。影响过滤效果的主要因素为PAC载量和混凝剂投加量,当混凝剂T3010和聚氯化铝的投加量分别为0.09mg/L和2.5mg/L,PAC载量为2-3g/L滤料时,载PAC过滤处理浊度为20-40NTU的微污染原水的效果达到最佳,对CODMn和浊度都具有很好的去除效果。Z河水作为原水的试验结果表明:载PAC过滤对河水浊度、UV254、CODMn的去除率分别为97%-97.9%、50.9%-63.4%、68.5%-71.4%。