针对金刚石钻头的岩石研磨性测定方法

针对石油钻井地层岩石研磨性试验评价问题,根据金刚石钻头的磨损机制,改装试验装置,研制标准磨损件,优选试验规程,提出以标准磨损件研磨破碎单位体积岩石的磨损体积作为岩石研磨性指标,建立一套岩石研磨性测定方法。试验测定石油钻井地层代表性岩石的研磨性指标。通过研磨性试验,优选出标准磨损件的金刚石体积分数为25%,粒度为0.3 mm,胎体配方为酚醛树脂55%、Cu 25%、Cr2O38%、Zn O 6%、Si C 5%、空隙1%(体积分数)。优选出的试验钻压为500 N,转速为198 r/min,排量为0.2 L/s。试验中代表性岩石的研磨性指标数值为0.80~45.78,取以2为底的对数值作为研磨性级值,将中国石油钻井地层岩石的研磨性分为6级。     

Effect of sintering on the relative density of Cr-coated diamond/Cu composites prepared by spark plasma sintering

Cr-coated diamond/Cu composites were prepared by spark plasma sintering. The effects of sintering pressure, sintering temperature, sintering duration, and Cu powder particle size on the relative density and thermal conductivity of the composites were investigated in this paper. The influence of these parameters on the properties and microstructures of the composites was also discussed. The results show that the relative density of Cr-coated diamond/Cu reaches ~100% when the composite is gradually compressed to 30 MPa during the heating process. The densification temperature increases from 880 to 915℃ when the diamond content is increased from 45vol% to 60vol%. The densification temperature does not increase further when the content reaches 65vol%. Cu powder particles in larger size are beneficial for increasing the relative density of the composite.     

数控单点金刚石切削非轴对称光学镜面

切削加工非轴对称光学镜面。方法用压电陶瓷微位移伺服刀架作执行机构,以金刚石为切削刀具,在自行设计的微机控制加工系统上进行切削加工实验。工件材料的黄铜,所加工的曲面满足光学成像系统中的像差补偿的射镜面－Ｚｅｍｉｋｅ方程。     

氧化铝陶瓷／金刚石膜复合材料的表征及介电性质研究

采用ＭＰＣＶＤ和ＨＦＣＶＤ在氧化铝陶瓷基片上沉积金刚石薄膜,用抛电镜,Ｘ躬一衍射和Ｒａｍａｎ散射分析表征了沉积膜的质量,并测这和分析了氧化铝／铝金刚石膜复合材料的介电性质。     

金刚石拉丝模激光打孔机的研制

报道了金刚石拉丝模激光孔机的整机结构,介绍了该机的激光器系统,光学系统,精密工作台,检测系统和微机控制系统的性能,简述了打孔的原理及其打孔的试验结果。     

热丝法批量制备金刚石涂层钻头参数仿真优化

基于有限容积法,研究了采用热丝化学气相沉积法常规工艺在批量化YG6硬质合金钻头工作表面制备金刚石涂层过程中基体表面的温度场分布状况,并通过测温对照试验验证了仿真方法及仿真结果的合理性和正确性.在传统的等间距热丝排布方式基础上系统研究了不同热丝参数(间距D、长度L、半径r、温度T和高度H)对基体温度场分布的影响,并进一步提出了不等间距的热丝排布形式以提高批量化基体表面温度场分布的均匀性,据此确定了用于批量制备金刚石涂层钻头的最优沉积参数.采用最优参数批量制备的金刚石涂层钻头具有较好的涂层质量和一致性,进一步验证了基于仿真的沉积参数优化方法的可靠性.     

建材加工用孕镶金刚石工具的磨损与控制

为了有效控制孕镶式金刚石工具的磨损行为和界面磨擦机制,以便高效率低成本加工建筑材料,综合分析了锯切加工中磨擦效应的特征以及如何使摩擦降低到最低程度,对加工过程中能量特征的定量分析表明,用于形成切屑的能量几乎可忽略;大约三分之一的能量消耗于岩屑流体与结合剂之间的作用,其余能量量消耗于塑性耕犁,优化和控制工具磨损主要是控制岩屑能耗和有效地控制磨粒达到其极限最佳切除负荷以抑制塑性耕犁效应。     

金刚石小锯片真空烧结技术

通过分析真空状态下金属的露点,得到真空烧结时比较理想的真空状态,并比较了真空烧结也保护气氛烧结后金刚石节块的综合性能。     

Optical characterization of single-crystal diamond grown by DC arc plasma jet CVD

Optical centers of single-crystal diamond grown by DC arc plasma jet chemical vapor deposition (CVD) were examined using a low-temperature photoluminescence (PL) technique. The results show that most of the nitrogen-vacancy (NV) complexes are present as NV-centers, although some H2 and H3 centers and B-aggregates are also present in the single-crystal diamond because of nitrogen aggregation resulting from high N₂ incorporation and the high mobility of vacancies under growth temperatures of 950-1000℃. Furthermore, emissions of radiation-induced defects were also detected at 389, 467.5, 550, and 588.6 nm in the PL spectra. The reason for the formation of these radiation-induced defects is not clear. Although a Ni-based alloy was used during the diamond growth, Ni-related emissions were not detected in the PL spectra. In addition, the silicon-vacancy (Si-V)-related emission line at 737 nm, which has been observed in the spectra of many previously reported microwave plasma chemical vapor deposition (MPCVD) synthetic diamonds, was absent in the PL spectra of the single-crystal diamond prepared in this work. The high density of NV- centers, along with the absence of Ni-related defects and Si-V centers, makes the single-crystal diamond grown by DC arc plasma jet CVD a promising material for applications in quantum computing.     

Recovery of valuable metals from waste diamond cutters through ammonia-ammonium sulfate leaching

Copper and zinc were recovered from waste diamond cutters through leaching with an ammonia-ammonium sulfate system and air as an oxidant. The effects of experimental parameters on the leaching process were investigated, and the potential-pH (E-pH) diagrams of Cu-NH₃-SO₄2--H₂O and Zn-NH₃-SO₄2--H₂O at 25℃ were drawn. Results showed that the optimal parameters for the leaching reaction are as follows:reaction temperature, 45℃; leaching duration, 3 h; liquid-to-solid ratio, 50:1 (mL/g); stirring speed, 200 r/min; ammonia concentration, 4.0 mol/L; ammonium sulfate concentration, 1.0 mol/L; and air flow rate, 0.2 L/min. The results of the kinetics study indicated that the leaching is controlled by the surface chemical reaction at temperatures below 35℃, and the leaching is controlled by diffusion through the product layer at temperatures above 35℃.