光学非球曲面器件的超精密磨削加工技术研究

为磨削加工出高精度、高质量的光学非球曲面器件。详尽分析了砂轮的安装及半径等误差对零件加工精度的影响。设计研制出了一套非球曲面磨削系统 ,并用它进行了实验研究。实验结果表明 :要获得高精度的非球曲面器件 ,只有当金刚石砂轮的平均磨粒尺寸低于 10 μm ,并在采用较高的砂轮线速度和较小的进给量的情况下 ,才能实现光学非球曲面的超精密磨削加工 ,经过各种磨削参数的优化选择 ,其非球曲面最终的零件轮廓精度为 0 4 μm ,表面粗糙度Ra优于 0 0 1μm。     

平行磨削非轴对称非球面光学元件表面形貌

结合砂轮表面仿真及磨削过程的运动学仿真获得工件表面轮廓、形貌和粗糙度预计,可以作为磨削过程中的理论依据,是精密磨削加工技术中主要的研究内容之一。平行磨削技术是加工非轴对称非球面光学元件的重要手段,而相关的仿真过程报道还很少。提出一种基于平行磨削的精密磨削加工非球面表面生成的仿真方法,该方法主要包含使用高斯方法生成具有不同统计学特征的随机砂轮表面形貌,建立单磨粒运动轨迹方程和圆弧砂轮细分后与工件表面点接触的运动关系,据此给出平行磨削加工表面生成的数值算法,并对不同加工参数下的工件表面形貌进行仿真。仿真结果和测量结果的一致性验证了所给算法的正确性和有效性     

轨迹成型法加工光学零件磨床中的微进给电控装置的研究

本文提出了一种在轨迹成型法加工光学零件磨床上实现脆性材料超精密磨削的微进给电控装置。试验表明,在轨迹成型法加工光学零件磨床上应用本装置对光学透镜进行磨削后,工件表面粗糙度可达Ｒａ＝０．０２μｍ,能够达到光学零件精磨的粗糙度要求。     

光学零件制造工艺(一):金刚石固着磨料精磨机理

本文表明金刚石磨具的磨削机理取决于玻璃的性质、磨削液的酸碱度以及磨料结合剂的化学、机械性能。掌握此机理,对用金刚石磨具加工精密光学零件表面的实用化很有必要。试验发现在多数情况下是裂纹机理?非塑性划痕机理。     

激光扫描在工件表面检测中的应用方法

为了获取磨削工件表面特征信息，提出一种基于激光扫描的磨削工件表面检测方法。利用机械臂带动激光传感器扫描放置在激光测量平面中的磨削工件，从而获得工件在激光测量平面中的三维坐标信息，通过相邻2个扫描点之间的高度变化求出工件边界点的三维坐标信息，结合x轴和y轴坐标的极值点利用最小二乘法拟合出工件边界在激光测量平面中的解析式，进一步求出附着在工件上的坐标系相对于激光测量坐标系的位姿，最后利用工件在激光测量坐标系中的位置矢量信息得出其表面特征信息。实验结果表明，利用该方法对工件表面进行检测，得到工件表面检测误差为0.11 mm，检测平均时间在1 s内，满足工件表面特征检测要求。     

光学薄膜表面复型电子显微照片的计算机处理

用计算机处理薄膜表面复型电子显微照片,得到表面高度轮廓,提出了计算机定标方法,并计算了薄膜表面微结构参量.     

黑腔芯轴平台微细电火花加工技术

采用电火花成型加工技术,在黑腔芯轴侧表面加工平台。采用白光干涉仪对平台表面轮廓及粗糙度测量,结果表明:平面部分表面粗糙度小于0.5μm,最大峰谷高度小于15μm。通过奥林巴斯测力显微镜对平台尺寸测量,结果表明:平台的轴向尺寸加工精度可控制在±10μm,同一电极加工的平台尺寸一致性可控制在±2μm。分析了电极损耗对零件形状精度的影响规律以及平台表面粗糙度的影响因素,并通过负极性加工去除电极损耗对平台尺寸精度的影响。     

激光三角测量中物面反射光斑重心偏移的修正

在进行激光(单)三角测量时,投影光束轴线的偏摆或投影光束在物面反射率不均匀处反射光斑重心的偏移会造成物面轮廓高度的测量误差。提出了采用双三角光路修正投影光束轴线偏摆和投影反射光斑重心偏移的方法,推导了修正公式;通过对物面反射率突变处轮廓高度的测量实验,验证了修正方法及公式的正确性;对灰度条模板表面轮廓进行双三角测量,轮廓高度均方根偏差小于0.07 mm。     

微磨削斜面光纤透镜平面度试验研究

为了研究微磨削参数对斜面光纤透镜平面度的影响,减小微磨削方法加工斜面光纤透镜的平面度误差,采用正交试验法对直径Ф125 μm单模光纤的30°斜面光纤透镜的微磨削进行了试验。结合微磨削的磨削力模型和材料力学弹性梁变形理论, 分析微磨削过程中随着磨削用量的变化所导致的光纤透镜被磨削斜面的平面度的变化规律。理论分析和实验结果表明:光纤悬伸长度对斜面光纤透镜平面度的影响最大,增大光纤悬伸长度将导致较大的斜面光纤透镜平面度的轮廓误差,恰当的磨削用量组合能够获得较小的平面轮廓误差。通过试验磨削出了平面度误差为3 μm的30°斜面光纤透镜。     

光学零件粗磨整平工艺

<正> 一、概述PM500铣磨机的使用大大提高了粗磨整平工艺的机械化程度。但由于机床本身的精度以及磨轮、磨削量、进给量、冷却液等多方面因素的影响,粗磨光学零件之光洁度一般只能达到220~#～240~#砂面。国内粗磨平面一般采用的磨轮粒度均在JR60~#～100~#之间,其浓度为100%。粗磨完工所要求的零件表面光洁度等级一般为▽6。从我国粗磨平面的特点来看,一般要去除较大的加工余量,单面余量多在2～3毫米之间,有的零件磨削第一面时其余量竟达5毫米以上。这势必要求金刚石磨轮具有良好的磨削性能,也就是磨轮应选用青铜结合剂且粒度应较粗。实践证明,粒度在80~#～100~#的磨轮由于其磨削力小,用于PM500铣磨机是不合适的,目前普遍采用的粒度为60~#～70~#的金刚石     

非球面碳化硅反射镜的加工与检测

为了获得高精度非球面碳化硅(SiC)反射镜,对非球面碳化硅反射镜基底以及改性后碳化硅反射镜表面的加工与检测技术进行了研究。介绍了非球面计算机控制光学表面成型（CCOS）技术及FSGJ-2非球面数控加工设备。采用轮廓检测法和零位补偿干涉检测法分别对碳化硅反射镜研磨和抛光阶段的面形精度进行了检测,并采用零位补偿干涉检测法及表面粗糙度测量仪对最终加工完毕的碳化硅反射镜的面形精度和表面粗糙度进行检测。测量结果表明：各项技术指标均满足设计要求,其中非球面碳化硅(SiC)反射镜实际使用口径内的面形精度（RMS值）为0.016λ(λ=0.6328μm）,表面粗糙度（RMS值）为0.85nm。     

Study on sapphire removal for thin-film LEDs fabrication using CMP and dry etching

Mechanical grinding, chemical mechanical polishing (CMP) and dry etching process are integrated to remove sapphire substrate for fabricating thin-film light-emitting diodes. The thinning of sapphire substrate is done by fast mechanical grinding followed by CMP. The CMP can remove or reduce most of the scratches produced by mechanical grinding, recovering both the mechanical strength and wafer warpage to their original status and resulting in a smoother surface. The surface morphology and surface roughness on grinded and polished sapphire substrate are measured by using atomic force microscopy (AFM). The etch rates of sapphire by BCl₃-based dry etching are reported. Pattern transfer to the physical and chemical stability of sapphire is made possible by inductively coupled plasma (ICP) etch system that generates high density plasma. The patterning of several microns period in sapphire wafer by using a combination of BCl₃/Ar plasma chemistry and SiO₂ mask is presented. The anisotropic etch profile formed on sapphire wafer is obtained from scanning electron microscopy (SEM) images.     

Heat and mass transfer at gas-phase ignition of grinded coal layer by several metal particles heated to a high temperature

Characteristics of gas-phase ignition of grinded brown coal (brand 2B, Shive-Ovoos deposit in Mongolia) layer by single and several metal particles heated to a high temperature (above 1000 K) have been investigated numerically. The developed mathematical model of the process takes into account the heating and thermal decomposition of coal at the expense of the heat supplied from local heat sources, release of volatiles, formation and heating of gas mixture and its ignition. The conditions of the joint effect of several hot particles on the main characteristic of the process–ignition delay time are determined. The relation of the ignition zone position in the vicinity of local heat sources and the intensity of combustible gas mixture warming has been elucidated. It has been found that when the distance between neighboring particles exceeds 1.5 hot particle size, an analysis of characteristics and regularities of coal ignition by several local heat sources can be carried out within the framework of the model of “single metal particle / grinded coal / air”. Besides, it has been shown with the use of this model that the increase in the hot particle height leads, along with the ignition delay time reduction, to a reduction of the source initial temperatures required for solid fuel ignition. At an imperfect thermal contact at the interface hot particle / grinded coal due to the natural porosity of the solid fuel structure, the intensity of ignition reduces due to a less significant effect of radiation in the area of pores on the heat transfer conditions compared to heat transfer by conduction in the near-surface coal layer without regard to its heterogeneous structure.     

Research on the interference fringe contrast in ground glass shape measurement

To measure the ground glass surface shape, the oblique incidence method applied using a Fizeau interferometer. Interferograms with sufficient contrast values are needed during the measurement. The formula to calculate the fringe contrast in ground glass shape measurement is derived to give an optimum incident angle for the ground glass with different surface roughness. Four specimens grinded by abrasives numbered #400, #700, #1500 and #2000 are measured, using aluminum coated mirror as the reflective flat in the experiment. The minimum incident angles of the four specimens are 83°, 82°, 76° and 75° respectively. The contrast values of the interferograms with the specimens at different incident angles are measured using phase shifting interferometry and the results match the theoretical ones. The oblique incidence method can be used to measure ground glasses grinded by #400 abrasive and finer ones. A sufficient contrast can be achieved with the incident angle slightly greater than the minimum angle.     

研磨影响粘土结构的红外光谱研究

将高岭石和蒙石两种粘土矿物分别用干法和湿法连续研磨,通过不同研磨时间的各粉城叶变换红外光谱（ＦＴ－ＩＲ）的实测和比较,发现干法研１２ｈ高岭石和蒙脱古老珠结构均开发改变,经４２ｈ高岭石的层状结构完全破坏,而经２４ｈ蒙脱石的层状结构即被破坏,但在湿法条件下研磨５４ｈ,它们的结构均无明显变化。由此可见,湿法研磨比干法好,文中还初步探讨了研磨影响粘土结构的原因。     

Feasibility study to investigate diffusion of Fe in Si using a Mössbauer spectroscopic microscope

A prototype Mössbauer Spectroscopic Microscope is applied for the feasibility study of ⁵⁷Fe impurity diffusion in Si wafers. A 2nm- ⁵⁷Fe deposited Si wafer is annealed at 430 °C for 1 hour, and subsequently the 1/3 area of the wafer is further grinded with an angle of 6 degrees to the original surface to get a higher depth resolution for the mapping. Subsequently, the mapping images for Fe\(_{\text {sub}}^{\mathrm {0}}\), Fe\(_{\text {int}}^{\mathrm {0}}\), and Fe\(_{\text {int}}^{\mathrm {+}}\) states are measured separately for the two different areas: one area (A) along the grinded surface, and the other (B) along the original wafer surface crossing through the ⁵⁷Fe-deposition boundary. By integrating the mapping intensity the diffusivity of each Fe component along the two different directions can be evaluated and compared with an average Fe diffusivity in Si, which is measured by EDS mapping data obtained for the same area.     

Features of different honeys identified by acoustic method

In this paper a series of experimental piezoelectric spectra of Zn_1-x-yBe_xMn_ySe (y = 0.05, x = 0.05, 0.10, 0.15) crystals are presented and discussed. Three groups of samples exhibiting different composition with different surface treatment: grinded, polished and etched were prepared. The influence of a different surface treatment on piezoelectric amplitude spectra are discussed with in model taking into account the presence of defects located on the surfaces of the samples.     

轻质碳化硅反射镜抛光过程镜面变形影响的研究

轻量化的碳化硅反射镜有自己独特的结构特点,加工中的变形与传统实体反射镜不同,对加工后的面形结果有独特的影响。对一直径为318mm的轻量化碳化硅反射镜进行了传统的研磨抛光,由于镜面变形对抛光结果带来了很大的影响,其面形误差的RMS值在0.048λ(λ=0.6328μma)左右就不再收敛。对抛光状态的镜体进行了有限元分析,探讨了减轻镜面变形对抛光结果影响的方法。采用计算机控制小磨头对该反射镜进行了确定性抛光,有效地降低了镜面形变的影响,使面形满足了精度的要求。     

三氯异氰尿酸红外光谱测绘方法探讨

本文对ＫＢｒ压片法、ＫＣｌ压片法以及萨特勒图谱采用的，糊剂法所绘制的三氯异氰尿酸的红外光谱进行了分析、对照。ＫＣｌ压片法克服了溶剂的影响，简单、直观地体现了物质的精细结构。同时，将三氯异氰尿酸分别与ＫＣｌ、ＫＢｒ研磨，和三氯异氰尿酸纯品进行了紫外－可见吸收光谱对照。实验发现，与ＫＢｒ研磨的三氯异氰尿酸和纯品的吸收峰有差异，而与ＫＣｌ研磨后的三氯异氰尿酸和纯品一致，说明结构未发生变化。因此，认为ＫＣｌ压片法是绘制三氯异氰尿酸红外光谱较好的方法。     

基质固相分散高效液相色谱法检测河豚毒素

建立了河豚鱼肉中河豚毒素的基质固相分散萃取的提取方法,并采用高效液相色谱-二极管阵列检测器进行测定。通过样品前处理的优化,确立选取0.5g样品与2.0g阳离子交换(SCX)吸附剂混合研磨,并采用10mL 5%氨水:甲醇溶液(5:95,V/V)作为洗脱剂。经HPLC-PDA检测,结果表明,河豚毒素在1—100mg/L浓度范围内呈现良好的线性关系(R2=0.9990),检出限为3.8ng,定量下限为12.7ng;加标回收率为77.9%—108.1%,RSD为2.23%—5.45%。该方法操作简单、耗时少,符合河豚毒素分析检测的要求。