某钒钛磁铁精矿深度还原-磁选试验研究

以河北承德某铁品位为61.08%，TiO2品位为7.66%的钒钛磁铁精矿为研究对象，进行了钒钛磁铁精矿深度还原-磁选试验研究。考察了还原温度、还原时间、C/O摩尔比、CaCO3添加量对还原产物和分选指标的影响。在还原温度为1350℃、还原时间120min、C/O摩尔比2.5、CaCO3添加量为16%、磁选场强为85mT的条件下，可以得到全铁品位为87.19%、铁回收率为82.62%的磁性产品和TiO2品位18.76%、TiO2回收率为79.40%非磁性产品。由还原产物的金属化率与XRD分析得知，钛磁铁矿向铁氧化物、钛氧化物和金属铁的转化较难发生，适当增加CaCO3的用量，能促进钛磁铁矿向CaTiO3、铁氧化物和金属铁的转化。      

Preparation and mechanism of active Mo–Mn metallization on ZTA particles surface and interfacial bonding of reinforced iron matrix composite

ZrO₂ toughened Al₂O₃ particles (ZTAp) have poor wettability with iron, and therefore some defects are easily formed at the interface between ZTAp and iron matrix, which may lead to material failure. This paper illustrates that the ZTAp were modified on the surface by the active Mo–Mn metallization, and thus, they were used as the reinforcing phases to prepare the iron-matrix composite (ZTAp/Fe composite). It is concluded that the sponge-like skeleton structure was formed on the surface of ZTAp after the metallization. The interface of ZTAp/Fe composite, which has been proved to have bearing and transitional capacity by scratch test, was formed by chemical bonding with elemental diffusion, besides mechanical bonding. The metallization mechanism of elemental diffusion can be explained by the migration of glass phase, and the elements diffusion between the interface and iron matrix is to form solid solution.     

The dielectric,thermal properties and crystallization mechanism of Li–Al – B–Si – O glass – Ceramic systems as a new ULTCC material

Li–Al–B–Si–O (LABS) glass-ceramics with a sintering temperature of 600 °C were studied for ultra-low temperature co-fired ceramics (ULTCC) applications. The crystal phase of LABS glass-ceramics is dendritic β-spodumene. The permittivity and dielectric loss of LABS glass-ceramics are ε_r = 5.8 and tgδ = 1.3 × 10⁻³ at 10 MHz, respectively. The coefficient of thermal expansion (CTE) of LABS glass-ceramics is 3.23 ppm/°C, which is close to that of silicon. The dielectric and thermal properties of LABS glass-ceramics are closely correlated to the degree of its crystallization. The permittivity decreases continually while the dielectric loss decreases first and slightly increases with the increasing of crystallization of β-spodumene. The CTE of LABS glass-ceramics decreases as β-spodumene crystallized from LABS glass. The crystallization kinetic and mechanism of LABS glass-ceramics indicate that the β-spodumene crystallizes in a two-dimensional interfacial growth mechanism due to the migration of Li-ions. The diffusion coefficients derived from energy-dispersive X-ray spectroscopy (EDS) results indicated that both Al and Ag electrodes have good compatibilities with ULTCC tapes, which could reduce the cost of multilayer electro-ceramic devices dramatically by using the ULTCC and base metallization.     

工艺参数对氮化铝陶瓷表面激光金属化层电阻的影响

目的 提高氮化铝陶瓷表面激光金属化层的导电性能。方法 采用正交试验设计方案,使用30 W纳秒光纤激光打标机制备了氮化铝陶瓷表面激光金属化试样,测量了金属层的电阻。通过极差分析和方差分析方法分析了激光工艺参数及其交互作用对氮化铝陶瓷表面激光金属化层电阻值的影响规律。结果 在本研究激光工艺参数及其取值范围内,激光功率对氮化铝表面激光金属化层电阻的影响最为显著,增大激光功率有利于降低氮化铝表面激光金属化层的电阻值。采用优化工艺参数(激光功率30 W、频率30 kHz、扫描速度100mm/s)单次激光扫描制备激光金属化层的电阻为2.25?/mm。随着重复扫描次数的增加,功率不同的激光表面金属层的电阻值向相反方向转变：小功率激光表面金属层电阻值随扫描次数增加而迅速减小,大功率激光表面金属层电阻值随扫描次数增加而增大。经10次重复扫描后,激光功率3 W(相应的激光能量密度约为15.3 J/cm²)激光金属化层的电阻值低于功率分别为30 W和18.75 W激光金属化层的电阻值。结论 采用30 W激光单次扫描,或者采用3 W激光多次扫描,有利于提高氮化铝表面激光金属化层的导电性。     

某锡铜硫化矿半自磨半工业试验研究

采用1 800×610 mm自磨机对云锡大屯选矿分公司处理的锡铜硫化矿进行半自磨半工业试验研究,通过对松树脚锡铜硫化矿进行磨机台时处理量、磨机转速、磨矿浓度、钢球充填率条件试验及连续稳定试验,结果表明,锡铜硫化矿采用半自磨工艺取代传统三段一闭路碎矿工艺是可行的,磨机排矿产品中新增-0.019 mm锡石过粉碎金属率可控制在较低的范围内。     

New antenna design approach – 3D polymer printing and metallization. experimental test at 14–18 GHz

This paper proves a new approach for rapid prototyping of radio antennas through 3D printing and chemical metallization. For this purpose, a standard metal pyramidal horn prototype is compared with its 3D printed replica. Three different 3D polymer printers are tested. The printed samples are assessed nondestructively by an X-ray Industrial Computed Tomography (CT) scanner, and then metalized via chemical deposition and chemical-electrochemical deposition. Copper with two different layer thicknesses and nickel materials are deployed and verified as a metallization opportunity. Again the CT scanner, X-ray fluorescent analysis and nanoindentation technique were used to perform the metallization quality estimation. As a result, a qualitative polymer prototype was produced having weight of 13 g – ten times lighter than the original. The prototype was successfully metalized and was able to be soldered. The radio-measurement comparison with the metal original for frequencies 14–18 GHz showed no significant differences. Finally, a simple dynamometric test confirmed the bonding between the metal and the polymer. To the best of our knowledge this is the first known comprehensive analysis of the possibility to print 3D lightweight wideband polymer antenna prototypes with a stable chemical metallization and radio properties very close to the original at 14–18 GHz.     

陶瓷金属化Mo粉测试及球磨工艺

陶瓷金属化生产中的Mo粉,通过采用科学的球磨方法,根据经验及理论公式计算球磨过程的各个工艺参数,进行各项生产性试验测试分析,应用于生产,产品的抗拉强度及一次金属化层微观形貌均达到了理想的要求,并经多次试验重复,肯定了这一工艺改进的正确性。     

GLSI多层布线钨插塞CMP表面质量的影响因素分析

随着超大规模集成电路向高集成、高可靠性及低成本的方向发展,对IC工艺中的全局平坦化提出了更高的要求。在特大规模集成电路(GLSI)多层布线化学机械抛光(CMP)过程中,抛光质量对器件的性能有明显影响。研究了多层互连钨插塞材料CMP过程中表面质量的影响因素及控制技术,分析了抛光过程中影响抛光质量的主要因素,确定了获得较高去除速率和较低表面粗糙度的抛光液配比及抛光工艺参数。     

材料表面化学镀铜及其应用

化学镀铜作为优良的表面处理技术,在电子、机械、航空航天等工业中得到广泛应用.有关化学镀铜的机理及化学镀铜新工艺的研究是电子产品表面金属化研究的热点.介绍了化学镀铜的原理及其应用,指出了其所面临的主要问题和未来的主要研究方向.