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Liu J.-S.,Henan Huanghe Whirlwind Co. | Wang F.-S.,Henan Huanghe Whirlwind Co.
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2012

Based on longtime study and application of the belt type press and cubic press, their properties in high temperature and ultra high pressure synthesis of diamond were analyzed. The results showed that higher pressure, uniform temperature and small shape change in cell are the properties of belt type press system, and the cubic press system has the properties of low production costs and high production efficiency. At last, the suitable field of these two devices, and the problems of these two devices in producing superhard abrasive materials under high temperature and ultra high pressure were discussed.

Cao H.,Henan Huanghe Whirlwind Co. | Guo S.,Henan Huanghe Whirlwind Co.
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2015

A series of experiments were conducted to optimize the process of electroplating Cu&Ni onto diamond and solve the problem of Ni leakage. Results showed that after preplating, the diamond was totally covered by Ni, which just melted during following plating process. Further experiments indicated the reason, which was a displacement reaction between Cu and Ni. To solve this problem, two projects, namely to increase current and to preplate Cu, were proposed. It turned out that both projects worked, while each of them had its own advantages and disadvantages. ©, 2015, Zhengzhou Institute of Abrasives Grinding. All right reserved.

Wang S.,Henan Huanghe Whirlwind Co.
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2015

Finite element analysis model for static analysis was established with Ansys. Stress distribution and deformation in working situation were analyzed. The models were then transfered into parametric models and imported into Ansys Workbench. Hinge sleeve was analyzed on its structure character and stress situation. To optimize the design, volume of parts and stress value at big stress sites was set as targets with major structure dimensions, such as bottom arc R, lug width H, as design variables. Results showed that R value directly influenced stress on the bottom. Bottom stress decreased as R increased. When R reached 70 mm bottom stress kept stable. Stress decreased as H increased, but the volume would increase accordingly. D and d had little influence on stress but their influence on volume could not be ignored. ©, 2015, Zhengzhou Institute of Abrasives Grinding. All right reserved.

Hu J.,Yanshan University | Liu Y.,Yanshan University | Men J.,Yanshan University | Zhang L.,Yanshan University | And 2 more authors.
Solid State Sciences | Year: 2016

A new nanostructure photocatalyst, incorporating Ag and reduced graphene oxide (rGO) with LaMnO3-nanorods have been fabricated via two-step synthetic approaches by using Cetyltrimethyl Ammonium Bromide (CTAB) as a template via a simple hydrothermal reaction and the decoration of Ag nanoparticles is through a traditional silver mirror reaction. The characteristic of the materials are examined by XRD, TEM, FE-SEM and XPS. The results confirm that the LaMnO3 nanorods are perovskite phase and uniform dispersed on the surface of rGO. The Ag nanoparticles is deposited the surface of LaMnO3-nanorods with its metal form. The Ag/LaMnO3-nanorods/rGO exhibit an excellent performance in the photo-degradation of Direct Green BE under the UV-vis irradiation. As an electron capture agent, metal Ag can capture the e− that transported along the LMO-NR, thereby leading to effective separation of the e−-h+ pairs and accelerate the transfer of surface charge, which is further demonstrated by the Photoluminescence (PL) spectra, cyclic voltammetry (CV) and AC impedance spectra. © 2016 Elsevier Masson SAS

Wang Y.-C.,Henan Huanghe Whirlwind Co.
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2014

The impurities in a series of abrasive diamonds synthesized by using iron and nickel alloy as catalyst, ranging from low grade to high grade, were investigated by employing magnetic susceptibility tester, SEM/EDS and oxygen nitrogen analyzer. The results show that magnetic susceptibility of synthetic diamond is proportional to the mass ratio of the diamond ash and the diamond itself. The main impurities in the synthetic diamond are iron, nickel, magnesium, silicon, calcium, oxygen and nitrogen. With the decrease of the total amount of impurities in the diamond, all of the impurities except for nitrogen decrease, but share of silicon and calcium increase. This fact implies that there may be another way for silicon and calcium get into the diamond lattice in addition to accompanying metal inclusions. The higher the diamond grade the lower the oxygen mass fraction, while the nitrogen mass fraction shows no relationship with diamond grade. To further investigate the origin of impurities in the diamond, the graphite and catalyst used for synthesizing the diamond were analyzed, too. Using of high-purity graphite and catalyst may contribute to the synthesis of high purity diamond, but not necessarily the top diamond.

Hu J.,Yanshan University | Liu Q.,Yanshan University | Shi Z.,Yanshan University | Zhang L.,Yanshan University | And 2 more authors.
RSC Advances | Year: 2016

Developing low-cost catalysts for high-performance oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly desirable. Herein, LaNiO3 nanorods supported on reduced graphene oxide (LNO-NR/RGO) were synthesized via a hydrothermal method, and characterized by XRD, SEM, TEM, XPS, TG and BET. The results show that the LaNiO3 nanorods have a perovskite structure and good dispersion behavior on the RGO sheets. The catalytic activity of the composite for ORR and OER has been studied by using a rotating disk electrode (RDE) technique. LNO-NR/RGO shows better oxygen electrode potential, a maximum cathodic current density of -4.26 mA cm-2 at 1600 rpm was obtained, and the ORR mainly favors a direct four electron pathway. Compared with pure LaNiO3 nanorods and commercial Pt/C, LNO-NR/RGO is more active for OER, a lower onset potential for OER and a bigger anodic current at the same applied potential are observed. The cycle performance and the stabilities of LNO-NR/RGO toward charge/discharge are significantly higher than those of commercial Pt/C in zinc-air batteries. Such excellent catalytic activity is attributed to the synergistic effect between LNO-NR and RGO along with the 1D conduction in the composite. © 2016 The Royal Society of Chemistry.

Liu J.-S.,Henan Huanghe Whirlwind Co. | Wang S.,Henan Huanghe Whirlwind Co.
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2012

The basic principle and advantages of microwave sintering were introduced. The current situation of preparation for polycrystalline diamond compacts (PDC) were simply generalized. Several problems were analyzed and discussed including the microwave sintering behaviors of ceramic materials, WC-Co and diamond sintered compact. The possibility of applying microwave sintering technology in the production of super-hard material tools was preliminarily discussed.

Wang Y.-C.,Henan Huanghe Whirlwind Co.
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2013

The wear resistance of PCD is tested by sand blasting method. The new method uses a high-speed flow of SiC abrasive particles as the tool to wear the sample instead of SiC abrasive wheel in traditional method, and the mass loss of the sample in a given time or unit time is used to describe the wear resistance of the sample. In principle, as soon as the intensity of the abrasive flow is controlled tightly enough, the new method could provide reasonably accurate results. The influences of main parameters upon the testing result in the new method are investigated experimentally. The comparision experiments show that new method exhibited much higher accuracy than the abrasive wheel method.

Shao Y.-Q.,Ningbo Hanshang Hydraulic Co | Liu J.-S.,Henan Huanghe Whirlwind Co | Zhou S.-J.,Ningbo Hanshang Hydraulic Co
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2013

As a new pressure supercharger, double-acting hydraulic supercharger has been used in the cubic press. The working principle of double-acting hydraulic supercharger was introduced. The application examples in the cubic press were analyzed. The results showed that double-acting hydraulic supercharger used in the cubic press has the advantages of smaller size, lighter mass, lower cost and more stable performance and lower noise compared with ordinary supercharger. In addition, there is no limit on super pressure time and it is convenient to control the pressure.

News Article | November 25, 2016
Site: www.newsmaker.com.au

A superhard material is a material with a hardness level exceeding 40 gigapascals. Superhard materials are highly incompressible solids with high electron density and high bond covalency. The various products of superhard material include cemented carbides, tool steels, ceramics and diamond. Cement carbide is generally used in industrial applications for machining tough materials such as carbon steel or stainless steel. The superhard material market is segmented in the following three categories: monocrystalline superhard, composite superhard materials and super-hard materials and tools. Monocrystalline superhard materials include diamond and cubic boron nitride. Composite superhard materials include clad sheet for oil and gas, clad sheet for cutting tools, clad sheet and wire drawing die blanks used for coal and mining. Super-hard materials and tools include polycrystalline diamond drawing dies, diamond saw blades, diamond drill bits, diamond discs and diamond cutting tools. Due to their incomparable hardness, superhard materials can scratch and shape any object, hence it used in a wide range of industrial operations related to turning, cutting, drilling, boring and grinding. Superhard materials are used in many industries including aerospace, alternative energy, automotive, chemical processing, infrastructure and construction, die & mold, electronic, general machining, mining, oil & gas, paper & pulp, power generation, railroads and shipbuilding. Application of superhard material in these industries includes abrasive, coating, cutting tool, general medical, precision part, refractory parts, sensors, semiconductor fabrication, subsystem components and wear parts polishing. In 2013, affected by the insufficient demand from downstream petroleum, construction and metal cutting machine tool and due to the sluggish economy, superhard material and products industry’s growth was slowed down and many companies were facing high operating costs due to this reason. In view of this, SF Diamond Co., Ltd, BOSUN Tools Co., Ltd, Henan Huanghe Whirlwind Co., Ltd, and some other companies adopted number of measures to expand their existing production capacity and extend their industrial chain to enhance their operational capabilities. Asia-Pacific is the largest market for superhard material. China contributes the largest share of superhard material market in Asia-Pacific region generating about 90% of global output and become the top producer of manmade diamond. The superhard material market in China reached about USD 2 billion in 2013, accounting about 21.8% of global market share in superhard material. Market of superhard material in North America and Europe region is driven by improving economy, intensifying manufacturing activity and the ensuing rise in demand for machine tools that used for various industrial operations.

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