[成形过程仿真优化与集成计算材料工程]限定加热管布局的快速热循环注塑成形模具电加热系统优化

针对管道布局、最大允许能耗给定条件下快速热循环注塑成形（RHCM）注塑模具型腔表面快速均匀加热的问题，提出以单根加热棒热流密度为设计变量，以模具型腔表面升温效率和温度分布均匀性为目标，结合有限元模拟、响应面设计以及多目标粒子群优化技术来优化RHCM模具电加热系统。与优化前相比，加热系统优化后，模具型腔表面最大温差降低63.4%，加热系统总能耗降低9%。对比了不同注塑成形工艺条件下成形的平板塑件表面质量，结果表明，相对传统注塑成形（CIM）工艺，RHCM工艺将制品表面粗糙度Ra从320 nm降低到118 nm，并有效抑制了制品表面熔接痕、缩痕等缺陷；发现制品表面粗糙度与型腔表面对应点温度成负相关，说明优化后的型腔表面温度分布更有利于提升制品表面质量。     

微结构模芯的精密磨削及其在微注塑成形中应用

针对微结构聚合物元器件的批量化生产与制造效率低等问题，采用精密修整成V形尖端的金刚石砂轮，在自润滑性和脱模性良好的钛硅碳陶瓷模芯表面加工制造出形状精度可控的V沟槽阵列结构，然后利用微注塑成形工艺将模芯表面的V沟槽阵列结构一次成形复制到聚合物表面，高效注塑成形制造出倒V形阵列结构的聚合物工件。分析了微模芯的表面加工质量与形状精度，研究了熔体温度、注射速度、保压压力、保压时间等微注塑成形工艺参数对微结构聚合物注塑成形角度偏差和填充率的影响。实验结果表明：通过微细磨削加工技术和微注塑成形工艺可以高效率、高精度地制造出规则整齐的微结构注塑工件，注射速度对微成形角度偏差的影响最大，保压压力对微成形填充率的影响最大，微结构模芯的微细磨削形状精度值为4.05 μm，微成形的最小角度偏差和最大填充率分别为1.47°和99.30%。     

12CrNi3钢外锁止套局部表面激光淬火工艺

利用半导体激光宽带对12CrNi3外锁止套局部进行表面淬火处理,并对处理后的零件进行外观检验、显微组织观察、硬度检测分析和摩擦磨损试验。试验结果表明:采取定光斑方式,激光头到工件表面扫描区域中心点距离375 mm(离焦量为0),工件倾斜22°,激光头倾斜18°,温度1350 ℃,扫描速度9 mm/s,单道扫描后表面平整性最好。表面激光淬火硬化层为750～1000 μm,最浅处为443.1 μm,硬化区组织为极细小马氏体组织,硬度达600～700 HV0.2,是基体硬度的2倍左右, 约为渗碳+淬火态硬度的1.3倍,且相变硬化区耐磨性能明显提高。     

选区激光熔化316L不锈钢的各向组织与性能

对采用选区激光熔化(SLM)制备的316L不锈钢增材制造试样进行了横向、纵向力学性能与微观组织分析。结果表明,增材制造SLM试件亚结构组织由尺寸为0.4 μm左右的胞状组织所构成,组织之间无明显的成分偏析,纵向与横向拉伸强度分别达到808和713 MPa,在经过1050 ℃热处理后,原组织中部分胞状组织消失,纵向及横向强度分别下降到673 MPa及579 MPa,增材制造试样相对传统热轧试样(550 MPa)具有明显的强度优势。SLM试样组织中存在未熔合缺陷,缺陷几何形状的方向性对其在拉应力作用下连接成裂纹有显著影响。热处理后缺陷长度方向与拉伸应力平行的纵向试样伸长率达到47.5%,横向试样伸长率为20%,伸长率指标均显著低于热轧316L钢试样,未熔合缺陷是导致3D打印试件塑性指标降低的主要因素之一。     

激光散射法测定大方无烟煤粒度的测试条件的选择

利用激光粒度分布仪对大方无烟煤进行了测试，目的是为了选取测量过程中最佳测试条件。结果发现测试条件对试验结果的影响较大，特别是分散剂、超声时间、搅拌池泵转速对测试结果的影响尤为显著。最终确定了激光粒度分布仪测试样品的合理测试条件，即分散剂为无水乙醇，无烟煤折射率为1.66，吸收率为0.46，在搅拌池中的超声时间为180 s，搅拌池泵转速为1 600 r·min^-1。另外，取样方法中，试管法和四分法均具有良好的代表性。     

Wide-band,passively Q-switched Yb- and Tm-doped fibre laser using WSSe saturable absorber

A wide-band, passively Q-switched fibre lasers based on ytterbium- and thulium-doped fibre gain medium are proposed and demonstrated. The lasers employ a transition metal dichalcogenide, tungsten sulphoselenide as a saturable absorber (SA) which is prepared by mechanical exfoliation technique. By integrating the SA in the laser cavities, self-starting Q-switched at 1038 and 1982?nm are obtained. The generated pulses exhibit a microsecond pulse duration with few kilohertz repetition rate. The proposed SA has high potential as a new material to cater to the needs of various scientific, industrial and biomedical applications.     

排风扇前盖注射模设计

分析了排风扇前盖塑件的工艺特点,介绍了排风扇前盖注射成型模结构及模具的工作过程。     

Pure CuBi2O4 Photoelectrodes with Increased Stability by Rapid Thermal Processing of Bi2O3/CuO Grown by Pulsed Laser Deposition

A new method for enhancing the charge separation and photo‐electrochemical stability of CuBi₂O₄ photoelectrodes by sequentially depositing Bi₂O₃ and CuO layers on fluorine‐doped tin oxide substrates with pulsed laser deposition (PLD), followed by rapid thermal processing (RTP), resulting in phase‐pure, highly crystalline films after 10 min at 650 °C, is reported. Conventional furnace annealing of similar films for 72 h at 500 °C do not result in phase‐pure CuBi₂O₄. The combined PLD and RTP approach allow excellent control of the Bi:Cu stoichiometry and results in photoelectrodes with superior electronic properties compared to photoelectrodes fabricated through spray pyrolysis. The low photocurrents of the CuBi₂O₄ photocathodes fabricated through PLD/RTP in this study are primarily attributed to their low specific surface area, lack of CuO impurities, and limited, slow charge transport in the undoped films. Bare (without protection layers) CuBi₂O₄ photoelectrodes made with PLD/RTP shows a photocurrent decrease of only 26% after 5 h, which represents the highest stability reported to date for this material. The PLD/RTP fabrication approach offers new possibilities of fabricating complex metal oxides photoelectrodes with a high degree of crystallinity and good electronic properties at higher temperatures than the thermal stability of glass‐based transparent conductive substrates would allow.     

超低渗油藏在线分流酸化增注技术研究与应用

酸化是超低渗油藏最有效的增注措施之一，但由于储层物性差、非均质性强等问题，造成目前常规酸化措施普遍具有施工周期长、有效率低、有效作用距离短等不足，且酸化过程中存在指进现象和储层二次伤害。针对这一问题，选取鄂尔多斯盆地环江油田三叠系超低渗油藏为研究对象，提出了在线分流酸化技术，并配套研制了一种多元缓速螯合酸COA-1S和一种新型的水溶性分流剂COA-1P。通过室内评价实验和在线分流酸化模拟实验，发现该技术在缓速性、配伍性、水溶性、螯合能力和暂堵功能等方面均显著优于常规酸化；现场先导性实验结果表明，酸化后剖面吸水均匀程度从28.5%上升至50.9%，视吸水指数增加2倍左右，降压增注效果显著；同时，该技术还具有“不停井、不泄压、不动管柱、不返排”的特点，简化了常规分流酸化工序、降低了安全环保风险，是一种能够很好地适应超低渗油藏特征的酸化增注技术。     

Diagnosis of the surface morphology of laser-ablated materials using the weighted- DCT approach in laser speckle interferometry for application to plasma facing materials

To implement on-line, real-time monitoring for the surface morphology of Plasma-Facing Materials (PFMs) in tokamak, we developed a Laser Speckle Interferometry measurement approach. A laser ablation method was used to simulate the erosion process during Plasma-Wall Interactions in a tokamak. In the present investigation, we evaluated the results of laser ablation morphology changes on the surface of Mo material reconstructed by four different approaches (Flood-fill, Quality-guided, Discrete Cosine Transform (DCT) and Weighted-DCT). The morphology results measured by the weighted-DCT approach are very close to the measurement results from confocal microscopy with an average error rate within 7%. It is verified that the weighted-DCT algorithm has high accuracy and can efficiently reduce the influence of noise pollution coming from laser ablation, which is used as a proxy for erosion from plasma wall interaction. Additionally, the CPU computer time has been shortened. This is of great significance for the real-time monitoring of PFMs’ morphology in the Experimental Advanced Superconducting Tokamak (EAST) in the future.