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Quick Search     Adv Search   2022 Vol. 32, No. 03 Published: 2022-06-10   1 Research progress in extrusion direct writing technology of additive manufacturing Hot! LIN Tao，WANG Hao，WANG Xueting，LI Qianghua，SONG Ke，DUAN Jing，SHAO Huiping DOI: ：10.13228/j.boyuan.issn1006-6543.20220015 Extrusion Direct Writing (EDW) method can be used to prepare complex shape parts of polymer, metal, ceramic and composite materials. Due to the advantages of wide adaptability, flexible process and simple equipment, it plays an important role in additive manufacturing technology. According to the different states and principles of raw material, it can be divided into Fused Deposition Molding (FDM) and Direct Ink Writing (DIW). In this paper, the development and application of EDW at home and abroad in recent years were mainly reviewed in the fields of metals, ceramics, composites and magnetic materials. Furthermore, this review summarized the performance of parts made by EDW and concluded its advantages and disadvantages. The development and challenge of EDW technology in the future were proposed out. 2022 Vol. 32 (03): 1-8 [Abstract] ( 3 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 9 Application and prospect of metal additive manufacturing technology in aviation field Hot! XU Shijiao，QUAN Chunyi，YANG Kun，ZHAO Dong，HU Fuchang，DENG Xiguang DOI: ：10.13228/j.boyuan.issn1006-6543.20210140 As one of the most popular applied technologies in material processing, additive manufacturing has been widely studied and applied in the aviation field because of its advantages of shorter forming time, higher forming accuracy and more freedom during design compared to the traditional manufacturing method such as casting and forging. In this paper，five metal additive manufacturing methods were introduced from the aspects of technical theory, research status, and application in the field of aviation. The research and application status of metal additive manufacturing in the aviation field at home and abroad were analyzed. The significance of developing metal additive manufacturing in the aviation field was clarified and the future prospect of metal additive manufacturing was discussed. 2022 Vol. 32 (03): 9-17 [Abstract] ( 2 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 18 Refractory metal materials made by additive manufacturing and its application progress Hot! ZHANG Xin，LIN Xiaohui，GAO Xuanqiao，XUE Jianrong，YANG Yichao，CHANG Tian DOI: 10.13228/j.boyuan.issn1006-6543.20210177 The traditional preparation and processing of refractory metal materials have long cycle, low efficiency, and large loss. Moreover, with the increasing requirements of modern industry for the size, accuracy, and complexity of parts, it will be more difficult to prepare and process tantalum, molybdenum, tungsten, and other metals by traditional methods. The rapid development of additive manufacturing technology can solve these problems. This paper introduces the additive manufacturing technology and its classification suitable for the processing of refractory metal materials, as well as the application and development prospect of refractory metal materials by additive manufacturing method. 2022 Vol. 32 (03): 18-22 [Abstract] ( 5 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 23 Research progress of additive manufactured high strength steel Hot! FENG Lingbing，LIU Fenggang DOI: 10.13228/j.boyuan.issn1006-6543.20210136 High strength steel with excellent strength and toughness played an important role in aerospace and other fields. The large key heavy-duty components were difficult to forge and had high requirements for hot working, this limited its further development and application. Metal additive manufacturing technology can realize rapid forming of metal components with high performance and precision, which provides a new way for manufacturing the high strength steel. In this paper, the classification of metal additive manufacturing technology at present, the forming characteristics of additive manufactured high strength steel, and the microstructure evolution and mechanical properties of high strength steel were introduced. The results show that the process parameters have great influence on the density of additive manufacturing high-strength steel, width and height of cladding layer, and then affect the internal quality of forming components. Heat accumulation can make the interlayer microstructure become thicker, and at the same time the microstructure of different parts have different solid phase transformation, which makes the microstructure of high strength steel more complicated. Heat treatment can significantly improve the comprehensive mechanical properties of additive manufacturing high strength steel. Finally, the aspects that need further research in additive manufacturing high strength steel are prospected. 2022 Vol. 32 (03): 23-33 [Abstract] ( 4 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 34 Research progress on near-net-shape forming technology of titanium and titanium alloy powder Hot! HUANG Xiaogang，HE Yong，WANG Jian，CAO Xihao，LIANG Zulei，CHEN Xiaolong DOI: 10.13228/j.boyuan.issn1006-6543.20210125 Titanium and its alloy parts have better performance with lighter weight, which have broad application in aerospace, weapon equipment, automobile industry and other fields. Compared to the traditional method of metal forging and mechanical processing, near-net-shape forming of titanium and its alloy possess higher material utilization ratio and faster molding speed for complex structure manufacturing. In this paper, typical preparation techniques and characteristics of spherical titanium alloy powder for near-net-shape forming were introduced, among which gas atomization method was the most widely used due to its advantages of higher yield and lower manufacturing cost. The powder prepared by plasma rotating electrode process had the advantages of good surface quality, high density and narrow particle size distribution, which was very suitable for application in key fields. Plasma atomization had attracted much attention of the industry and industry chain because of achieving both high yield of fine powder and high powder quality. The research progress of near-net-shape forming technology of titanium and its alloy powder was reviewed, the research route of further improving the properties of parts based on microstructure regulation provided theoretical support for the development of materials and technology of near-net-shape forming of titanium and titanium alloy powder. It was proposed that unremarkable cost performance of the parts, low continuity of the whole manufacturing process and few available materials were the main problems in preparation of titanium and its alloy parts via near-net shape forming technology, and some solutions were given. Finally, future developments were analyzed, and cost reduction of powder manufacturing and development of new materials and process were considered to be the important research direction of titanium and titanium alloy powder near-netshape forming technology. 2022 Vol. 32 (03): 34-43 [Abstract] ( 8 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 44 Research progress on metal powder reuse of powder bed fusion Hot! HU Juan，Lü Xinfeng，SHEN Lida，MAO Yuyi，JIANG Wei，GAO Yintao DOI: 10.13228/j.boyuan.issn1006-6543.20210035 Powder bed fusing technology has been widely used in many fields due to its rapid ability to form complex structures as well as the high dimensional accuracy and good surface quality of the formed parts. However, compared with traditional manufacturing methods, this method is not cost efficiency. Powder reuse is one of the important ways to solve this problem, but whether the recycled powder can be used is affected by many factors. In view of this, the present paper first analyzes the factors that affect the powder reuse, and then based on the literature review, affects of different reuse strategy on the powder and the corresponding parts is analyzed, Finally, the future research recommendations are put forward. 2022 Vol. 32 (03): 44-48 [Abstract] ( 0 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 49 Numerical simulation of semi-solid powder compression process of Mg-6Zn alloy Hot! REN Jun，LUO Xia，CAI Xiaowen，FAN Zhou，HUANG Bensheng DOI: 10.13228/j.boyuan.issn1006-6543.20210077 Magnesium alloy has become the most promising bone implant and vascular stent materials due to its good biocompatibility, matched elastic modulus and biodegradability. However, the poor degradation performance and unclear metabolic mechanism of degradation products limit its further application. In order to meet the degradation adaptation of magnesium alloy, a novel powder metallurgy named semi-solid powder moulding was adopted to prepare the medical Mg-6Zn alloy. Semi-solid powder moulding is a near-net shape forming technique, which combines powder forming and semi-solid forming with one step. It has great advantages to prepare the alloys and its composites with low melting point and wide solidification range. In order to optimize the forming process and get excellent performance of Mg alloys, it is necessary to simulate the forming process in the preparation of medical Mg-6Zn alloy. As this technique simultaneously involves in deformation, solidification and densification, it has many difficulties in the simulation of forming process. This study gives a clue for the simulation of semi-solid powder moulding based on the Shima-Oyane model. At beginning, the constitutive equation of Mg-6Zn powder materials was deduced and improved based on the semi-solid compression experiments. The materials constants of Mg- 6Zn powder materials were obtained. This study simulated the semi-solid compression process of Mg-6Zn powder materials by MSC. Marc software. The relative density and displacement of powders were simulated and was proved by the experiments. The influence of forming temperature on the semi-solid powder moulding process was studied. The results show that the forming temperature has little effect on the relative density when the liquid fraction is less than 10%, and the relative density gradually increases and tends to be stable with the progress of compression. The stress of semi-solid powder moulding is concentrated at both ends of the edge of the cylindrical blank. The minimum stress locates in the "belly" area at both ends of the center and the edge of the cylindrical blank. The experimental results agree well with the simulated results. With the increase of liquid fraction higher than 10%, The difference between the simulated and experimental results are becoming larger and larger. This model has good reliability when the low liquid fraction is lower than 10%. However, the error is large with high liquid fraction. The liquid is the main factor making this error. A new model suitable for semi-solid powder molding needs to be established urgently. 2022 Vol. 32 (03): 49-56 [Abstract] ( 3 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 57 Preparation of Cr2(C,N) powders by carbothermal reduction-nitridation method in open system Hot! CHEN Zhenlei，MA Shiqing，ZHANG Luokun，WANG Yiman，JIAO Penggang，YANG Zhigang DOI: 10.13228/j.boyuan.issn1006-6543.20210082 Single phase Cr2(C,N) powder was prepared by carbothermal reduction nitridation method, with carbon black and chromium oxide as raw materials in an open system. By means of TG-DSC, XRD and SEM, the effects of synthesis parameters, including heating temperature, holding time and nitrogen flow rate on the preparation of Cr2(C,N) were studied. The results show that with the heating temperatures increase, the phase evolution follows the sequences of Cr2O3→(Cr2O3, Cr3C2 and Cr6.2C3.5N0.3)→Cr2(C,N). When temperatures reach 1 100 ℃, the single phase Cr2(C,N) powder can be obtained. The optimal parameters of synthesis Cr2(C,N) powders, with the prefer phase constitution, particle size and nitrogen content, are 1 200 ℃ for 2 h under the nitrogen flow rate of 2.5 L/min. It contributes to increasing the nitrogen content of Cr2(C,N), while increase synthesis temperatures, prolong holding time and improve the nitrogen flow rate appropriately. 2022 Vol. 32 (03): 57-62 [Abstract] ( 3 ) HTML (1 KB)  PDF  (0 KB)  ( 3 ) 63 Study on preparation and performance of small-size ZrO2 nozzle for powder production by gas atomization Hot! WANG Laiwen，YU Jianbin，MAWeikui，WANG Gang，DU Penghui，WANG Wenwu DOI: 10.13228/j.boyuan.issn1006-6543.20210147 The small-size ZrO2 nozzle bodies were prepared by hot injection moulding with Y2O3 stabilized ZrO2 and monoclinic ZrO2 as the main materials, the amount of Y2O3 is 2%, 4 % and 6% respectively. After degreasing, the body was sintered at 1 650, 1 700 and 1 750 ℃ for 5 h, respectively. The effects of sintering temperature and Y2O3 addition amount on the performance of small- size ZrO2 nozzle were studied, and the online service performance was compared. The results shows that with the increase of sintering temperature and Y2O3 content, the density and room temperature folding strength of the samples are gradually increased, the structure is more compact, the content of c-ZrO2 phase increases, and the linear expansion rate increases. The linear expansion rate of the sample with Y2O3 content of 6 % is significantly higher than that of the sample with Y2O3 content of 2 % and 4 %. The high stabilization interest rate and dense structure are not conducive to the thermal shock resistance of ZrO2 nozzles. The ZrO2 small-size nozzle prepared by adding 4% Y2O3 and sintering at 1 700 °C for 5 h has the best comprehensive performance and the best on-line service performance. 2022 Vol. 32 (03): 63-67 [Abstract] ( 2 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 68 Research on the pore distribution modeling and cutting characteristics of the cone ring of car synchronizer Hot! ZHANG Xiaofen DOI: 10.13228/j.boyuan.issn1006-6543.20210096 The auto synchronizer cone ring is a typical iron-based powder metallurgy part. It has large production batch and many difficulties in the cutting process with a lot of pore structures and hard particles inside the powder metallurgy parts. Intermittent load impact is produced in cutting procedure, which seriously affects the tool service life. In this paper, the porous characteristics of powder metallurgy materials are studied, the corresponding relationship between the density and pores of powder metallurgy materials is selected for modeling, the porosity of the material is deduced from the density, and the pore distribution law of the material is simulated by the normal distribution of random points. DEFORM 3D cutting simulation studies the changing laws of force and temperature during cutting of single-hole and porous materials. The calculation results show that the cutting stress caused by the pores fluctuates greatly, resulting in micro-impact fatigue damage; the pore structure causes the accumulation of heat and aggravates the oxidative wear of the cutting edge; it is the key factor that causes the rapid wear of the tool. 2022 Vol. 32 (03): 68-74 [Abstract] ( 2 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 75 Microstructure and mechanical properties of Cu-12Al-6Ni with graphite addition prepared by powder metallurgy Hot! DENG Zhenghua，YIN Haiqing，WANG Haibao，LI Wanquan，JI Anping DOI: 10.13228/j.boyuan.issn1006-6543.20200175 The effect of graphite on the microstructure and properties of Cu-12Al-6Ni alloy prepared by powder metallurgy was investigated. The results show that the number of pores, Al4Cu9, and NiAl phases in the structure increases with increasing of the graphite content. The sintering density, hardness and tensile strength of the alloy decreases as the graphite content increases. The friction coefficient and wear loss of the alloy first increases and then decreases with the increasing of the graphite content. When the graphite content is 0.5%, the friction coefficient reaches a maximum, and when the graphite content is 1%, the wear loss maximizes. When the graphite content is 2%, the wear loss of alloy is approximately 32% lower than that of the alloy without graphite. 2022 Vol. 32 (03): 75-80 [Abstract] ( 0 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 81 Study on the adsorption performance of HNO3 and NaOH modified coconut shell activated carbon Hot! LUO Feng，HUANG Bangfu，LI Jianli，WANG Zhuo，WANG Chunliang，WANG Defu DOI: 10.13228/j.boyuan.issn1006-6543.20210054 In order to improve the adsorption performance of activated carbon, coconut shell activated carbon was modified with nitric acid and sodium hydroxide. The iodine adsorption value of coconut shell activated carbon before and after modification was measured. The study shows that the iodine adsorption value of coconut shell activated carbon after nitric acid modification is reduced by 20.81%; After sodium hydroxide modification, the iodine adsorption value of coconut shell activated carbon is increased by 4.48%; the two modification methods have changed the overall adsorption capacity of coconut shell activated carbon, and NaOH modification can also enhance the non-polar and hydrophobic surface of the activated carbon. By changing the surface chemistry, the adsorption capacity of coconut shell activated carbon modified by sodium hydroxide is stronger than that of nitric acid modified activated carbon. Related research results can provide reference for the use of activated carbon to treat NOx and SO2 in industrial flue gas. 2022 Vol. 32 (03): 81-85 [Abstract] ( 0 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 86 Microstructure and properties of graphene/2024Al composites prepared by powder metallurgy Hot! PENG Yujie，LIU Pei，LIU Kunding，WANG Jie，WU Shuaikui，ZHOU Zheng DOI: 10.13228/j.boyuan.issn1006-6543.20210048 In this paper, graphene nanosheets and 2024Al alloy powder were used to prepare graphene /2024Al matrix composites with different contents by the method of cold isostatic pressing + vacuum sintering + hot extrusion. The microstructure and mechanical properties of graphene/2024Al with different contents were investigated by SEM characterization, EDS analysis and property tests. The results show that the graphene in the composite presents a random distribution after cold isostatic pressing and vacuum sintering, and the density of composite is relatively low in this case. But when the graphene/2024Al composite is hot-extruded, the graphene in the composite presents an aligned arrangement, and the density of composite is obviously enhanced. Then tensile strength of 0.5% and 1% hot-extruded graphene/2024Al composite reaches 290.6 MPa and 321.1 MPa, which is improved by 48.8% and 64.4% compared with the 2024Al matrix, respectively. These results show that the addition of graphene and the increase of graphene content can effectively enhance the tensile strength of graphene/Al composite. 2022 Vol. 32 (03): 86-90 [Abstract] ( 1 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 91 Research on microstructure and properties of SiC particle reinforced 2A02Al matrix composites Hot! DONG Haitao DOI: 10.13228/j.boyuan.issn1006-6543.20210104 The 30% SiCp/2A02A1 composite was prepared by hot-press sintering process. The sintered sample was hot pressed. The microstructure and fracture morphology of the composite were observed by OM, SEM and TEM, and the density and mechanical properties were measured respectively. The results show that the interface between SiCp/2A02A1 composite and reinforcement is well combined with clear and smooth boundry. After hot extrusion, the segregation of SiC particles decreases, and SiC is uniformly distributed in the matrix, and high density dislocation and subgrain are formed in the matrix. The density and mechanical properties of the composites increased significantly. After aging treatment, disc-shaped precipitation -Al2Cu phase is formed in the matrix of hot extrusion sample. 2022 Vol. 32 (03): 91-95 [Abstract] ( 2 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 96 A review of research on powder prepared by gas atomization Hot! ZHANG Xueliang，TAO Yu，JIA Jian，QU Jinglong DOI: 10. 13228/j. boyuan. issn1006-6543. 20210034 The research progress of gas atomization technology at home and abroad was summarized, including the influence of gas atomization parameters on the powder characteristics, the numerical simulation of gas flow structure, primary breakup of high-temperature melt and secondary breakup of droplets during gas atomization to provide some references for the further improvement of gas atomization technology. The quality of powder is related to the parameters of gas atomization. In a certain range, both increasing gas pressure, gas temperature, melt superheat and decresing melt diameter, melt flow rate will cause the power size decrease and improve the yeild rate of fine powder. The dynamic energy of atomization gas can be increased with increasing gas pressure and temperature, which is benefit for the melt breakup. Meanwhile, increasing the melt superheat will make the viscosity and surface tension of melt decrease, which will also promote the melt breakup. The gas atomization process is too complex to analyze through the ordinary experimental methods, so numerical simulation becomes an important way to describe the gas flow field, primary breakup of melt and secondary breakup of droplets during gas atomization process. The simulation results indicate that the gas flow field is consisted of a series of“Prandtl Meyer” waves, forming a“necklace-like”structure. The primary breakup of melt is mainly simulated by VOF (volume of fraction) model. And the secondary breakup of droplets is well described using DPM (discrete phase model) modle and the instability model of melt such as TAB model, KH model and KHRT model. Particle size distribution and particle morphology are closely related to the parameters of gas atomization such as gas pressure, gas temperature, melt superheat and melt flow rate. Selecting reasonable atomization parameter is the basis for preparing spherical powder with high quality. At present, the research on the gas atomization process, including the gas flow field, primary breakup of melt and secondary breakup of droplets, is mainly conducted by numerical simulation method. The existing theoretical models and algorithms can realize the simulation of the gas atomization process, but the understanding of the interaction between different atomization stages is still blank. In order to realize the mutual coupling analysis of different stages of the entire atomization process, optimizating the theoretical model and algorithm of gas atomization is improtant in the furture study. 2022 Vol. 32 (03): 96-106 [Abstract] ( 3 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 107 Research progress in the application of electrochemical biosensor detection technology for carbon nanocomposites Hot! MAO Zhaoming DOI: 10.13228/j.boyuan.issn1006-6543.20200120 This paper introduces voltammetry and the application of electrochemical biosensors, describes how carbon nanomaterials are incorporated into the construction of biosensors to adjust sensitivity and detection limits, and also presents enzyme-free and enzyme-containing carbon nanomaterial sensors for the detection of biomolecules such as dopamine, uric acid, proteins, enzymes and hydrogen peroxide, respectively. The current research status of carbon nanotube biosensors, graphene/carbon nanotube biosensors and graphene biosensors in related detection are highlighted. Finally, the future structure of biosensors, the limitations of current materials and how to use new materials to enhance the sensing ability are proposed. 2022 Vol. 32 (03): 107-111 [Abstract] ( 1 ) HTML (1 KB)  PDF  (0 KB)  ( 1 ) 112 Research progress of enzyme-free glucose sensors based on new nanomaterials Hot! ZHANG Lamei，CHEN Jinyan，GOU Ding DOI: 10.13228/j.boyuan.issn1006-6543.20200286 The detection method of glucose concentration has attracted much attention in the fields of medicine, food, bioengineering and so on. Compared with the currently used sensors, the enzyme- free glucose sensor is a promising method because of its flexible detection, stability, low cost, and reusability. With the study of functionalization and refinement of modern nanomaterials and the study of electrocatalytic reaction mechanism, the enzymefree glucose sensor can quickly and stably detect blood glucose concentration in the future, and promote the progress of medicine. Therefore, this paper mainly reviews the research status of nanomaterials in enzyme-free electrochemical glucose sensors in recent years from three aspects: metal nanomaterials, non-metallic nanomaterials and metal oxide nanomaterials, and introduces the excellent properties of new nanomaterials in enzyme- free glucose sensors. performance, and the future development trend and direction are prospected. 2022 Vol. 32 (03): 112-116 [Abstract] ( 6 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 117 Cutting tiles diamond circle blade bond study of replacing Co to reduce cost Hot! YANG Zhiwei，LIANG Fu，LIU Yibo DOI: 10.13228/j.boyuan.issn1006-6543.20210060 A lower cost superfine copper-cobalt-iron alloy powder was selected to replace the cobalt powder in the binder of diamond circular saw blade for wet cutting of high hard tile, and the influence on the performance of the saw blade was studied. The results showed that there was a certain decrease of the cutting speed of the product after substitution, but when the price of cobalt powder was higher than 400 yuan/kg, the cost performance of the product was significantly improved. the higher the substitution ratio, the more obvious the cost performance advantage. The superfine CuCoFe alloy powder is more suitable for general diamond tools when the price of cobalt powder is high. Cobalt powder has advantages in performance and is more suitable for professional diamond tools. 2022 Vol. 32 (03): 117-121 [Abstract] ( 2 ) HTML (1 KB)  PDF  (0 KB)  ( 3 ) 122 Cause analysis of foreign matter precipitation on the surface of ferrous P/M parts and countermeasures Hot! LI Ziyang，LUO Wenfeng，ZUO Xinlang，ZHANG Kun，ZHU Gang DOI: 10.13228/j.boyuan.issn1006-6543.20210032 Foreign matter on the surface of a powder metallurgy part of a compressor resulted in the failure of the product. The pores and oxides on the surface of the part were observed by scanning electron microscopy. The results showed that there were many open pores on the surface of the part after machining because of insufficient steam oxidation reaction inside the part. By analyzing the steam treatment process of the failed parts, it is found that the reason is the improper setting of steam treatment temperature and time, and further reveals the failure mechanism. By improving the powder proportion of matrix material, forming density and steam treatment technology, the problem of foreign matter precipitation on the surface of parts was effectively solved. 2022 Vol. 32 (03): 122-126 [Abstract] ( 2 ) HTML (1 KB)  PDF  (0 KB)  ( 2 ) 127 Analysis of difference in sputtering deposition effect of molybdenum target Hot! LIN Bingtao，WANG Na，YANG Minghui，WANG Chengyang，ZHANG Baohong，XIONG Ning DOI: 10.13228/j.boyuan.issn1006-6543.20210108 Molybdenum rods with different grain sizes were prepared by powder metallurgy method, and the target materials were processed. The microstructure and mechanical properties of the products were analyzed by metallographic technique and microhardness test, and the reasons for the differences in sputtering deposition effect of molybdenum during coating preparation were studied. The results show that the grains of molybdenum target are uniform and fine, and the larger the area ratio of grain boundary is, the better the sputtering deposition effect of molybdenum target is. The tensile strength, elongation and hardness of molybdenum target increase with the decrease of grain size. 2022 Vol. 32 (03): 127-130 [Abstract] ( 3 ) HTML (1 KB)  PDF  (0 KB)  ( 2 )

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