光纤激光轧辊毛化工艺参数研究

针对CO₂激光器和YAG激光器的种种不足,采用光纤激光毛化柔性工作站,对轧辊表面进行了不同尺寸和分布的毛化点彤貌加工。分析了光纤激光功率、脉冲频率、脉冲宽度、扫描速度、离焦量等工艺参数对毛化点形貌的影响。结果表明:通过合理匹配毛化工艺参数,能够得到精确可控的轧辊毛化形貌和满足生产要求的粗糙度,也可以实现相对无序的毛化点排列。     

Rigorous optical modeling and optimization of thin‐film photovoltaic cells with textured transparent conductive oxides

Typical thin‐film photovoltaic (PV) cells incorporate a textured transparent conductive oxide to enhance light trapping and efficiently harvest solar energy. Rigorous coherent optical simulations of these devices and a complete characterization of these textured films are a challenging problem because of the several orders of magnitude difference between the wavelengths of interest and the spatial dimension of the sample that needs to be evaluated. In this paper, a practical approach for rigorous and predictive modeling of optical properties of thin‐film PV cells incorporating a vast variety of light‐trapping structures including semi‐coherent textured films and patterned coherent structures is presented. In contrast to the existing semi‐empirical device models, it is demonstrated that the presented methodology can accurately predict the scattering properties of textured fluorine‐doped tin oxide and aluminum‐doped zinc oxide conductive transparent films. It is further shown that the optical response of single‐junction and tandem‐junction PV devices incorporating such films can also be predicted with good accuracy as compared with the measured results. Next, a methodology to identify the sufficient statistical fingerprints of semi‐coherent textured films that are needed to unambiguously predict the light propagation in thin‐film cells is presented. This comprehensive approach then lends itself to identifying the optimal surface morphology needed for strong light trapping. This rigorous approach automatically includes the effects of important loss mechanisms such as the surface plasmon‐enhanced absorption in textured metal surfaces that are otherwise very difficult to account for semi‐coherent approaches based on scalar scattering theory. Copyright © 2011 John Wiley & Sons, Ltd.     

中厚度织物用涤纶仿毛丝假捻变形工艺浅析

介绍了采用细旦多孔涤纶POY和FDY为原料,利用异收缩混纤技术原理,在日本TMT公司33H型假捻变形机上开发生产仿毛型涤纶丝的生产工艺。结果表明,选择合理的纺丝速度,拉伸比,速比,假捻角,第一热箱温度,第二热箱温度及二、三超喂率等工艺参数,可纺得性能优良的涤纶仿毛丝。其织物具有蓬松而富有弹性的手感、优雅自然的光泽及良好的穿着舒适性。     

Ni伴随WC颗粒复合沉积层的表面粗糙度和显微结构

The intermediate layer was prepared by nickel doped with WC particles electroplating.The parameters,including current density and temperature,were studied.The measured methods,which consisted of surface roughometer and SEM,were used to character the roughness and micrograph.Based on the results,it was shown that the optimized parameters of the composite were as follows,temperature 65 ℃,current density 5 A/dm2 and pH 6.5.In the range of optimized parameters,the roughness Ra was from 4.5 to 6.7 μm.From the SEM micrograph,the particles on the surface were well distributed.The nickel content,which affected the binding force,was determined by the electroplating time.     

多晶硅太阳电池表面绒面制备工艺优化

采用各向同性腐蚀法制备多晶硅绒面,利用正交实验法研究了不同腐蚀液配方中的HNO3、HF和缓和剂NaH2PO4·2H2O的含量对多晶硅太阳电池绒面的反射率和腐蚀速度的影响。结果表明:NaH2PO4.2 H2O溶液对腐蚀速度有着显著的影响,其次为HF溶液和HNO3溶液;对于反射率来说,其影响因素的重要性主次顺序为HF溶液、HNO3溶液、NaH2PO4·2 H2O缓和剂。在本实验条件下,最佳的酸腐蚀混合液配方为HF∶HNO3∶NaH2PO4.2 H2O=9∶1∶7,在该工艺条件下,制备的硅片绒面腐蚀坑较为均匀,反射率为17%左右。     

涤纶DTY退绕性能试验方法

通过模仿涤纶DTY在织布工厂的使用过程,制作简单试验装置,制定试验规程,对涤纶DTY进行退绕性能试验,验证原料、工艺、设备等加工条件变化时产品的退绕性能是否有影响,及时发现和解决问题,从而提高产品质量。     

Effects of core-yarn overfeed on texturing performance: comparison between air-jet and steam-jet texturing

The objectives of this research work were to investigate the use of high-pressure steam in order to replace air in the production of spun-like textured yarns and to investigate the optimum level of core-yarn overfeed ratio for steam-jet textured yarn for the application of sewing threads. An existing air-jet texturing machine was modified to supply either air or steam to the texturing nozzle. Using an identical nozzle, both air-jet and steam-jet textured yarns were manufactured. Loop instability and loop density increased and strength and tenacity decreased when the core-yarn overfeed was increased in both air-jet and steam-jet textured yarns. Steam-jet textured yarns have lower loop instability, lower loop density and higher tensile properties than that of the air-jet textured yarns. Sewability results show that for both air-jet and steam-jet textured sewing threads, core-yarn overfeed ratios of 5.5 and 8.3% give better sewability.     

Limiting speed of false-twist texturing: a possible explanation of the post-surging mode

The ¹ 1. Retired speed of false-twist texturing is limited by tension surging, which has been explained as flipping between a good pre-surging mode and an unsatisfactory post-surging mode. Fundamental research on the mechanics of rotating rods has shown that buckling occurs above a critical speed for a rod under a given torque and tension. In false-twist texturing, it is postulated that this leads to formation of buckles in the feed→spindle zone, which pass through the system giving rise to the irregular behaviour of the post-surging mode.     

拉深模激光毛化工艺参数实验研究

为改善拉深模摩擦和润滑条件,提高其使用寿命,提出使用激光毛化技术对其表面进行造型强化。通过实验对影响激光毛化效果的主要工艺参数进行研究,得到拉深模激光毛化的合适工艺参数范围,为拉深模激光毛化表面摩擦性能研究及毛化点尺寸优化奠定基础。     

Surface texturing of GaAs using a nanosphere lithography technique for solar cell applications

In this study, we present novel methods to texture the surface of GaAs substrates using the nanosphere lithography (NSL) technique that is based on arrays of SiO₂ nanospheres. Closed-packed arrays of SiO₂ nanospheres were formed on a benzocyclobutene (BCB) layer, followed by embedding SiO₂ nanospheres into the BCB layer. To texture the GaAs surface, three patterns were fabricated by nanosphere lithography. First, a convex pattern from the shape of the nanospheres was produced on the surface of GaAs. Second, a concave shape was produced on the surface of GaAs by additional wet etching to remove SiO₂ nanospheres. These two methods were found to be effective in reducing the reflectance to a range of 400-800 nm. Finally, the arrays of SiO₂ nanospheres were transferred onto the GaAs by dry-etching using a mixture of Cl₂ and BCl₃ gases, resulting in arrays of GaAs nanorods. The dry-etched surface structure showed the lowest reflectance.