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Journal of Central South University 2021年第10期28卷 3008-3017页

作者： S.H.HOSSEINI M.SEDIGHI School of Mechanical Engineering Iran University of Science and TechnologyTehran 16846-13114Iran

This paper investigates process parameter effects on microstructure and mechanical properties of the tubes processed via recently developed friction assisted tube straining(FATS)*** this purpose,design of experiment was used to arrange finite element analyses and experimental *** and experimental tests were executed by changing rotary speed,feed rate and die *** design results show that increasing feed rate and decreasing rotary speed enhance Zener-Hollomon(Z)parameter and decrease average grain size,while die angle has no considerable *** Z value reduces grain size and enhances flow stress of the processed samples,while the experiment with the highest Z value refines initial microstructure from 40 to 8μm and increases flow stress by 5 times.

关键词： friction assisted tube straining process parameter microstructure Taguchi method finite element simulation

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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Journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu G.G.Wang A.Hu Y.Li K.B.Thacker J.P.Weiler H.Hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada Global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(SY)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,Chemical Sludge(CSF),Physical Sludge(PSF)and Comprehensive Sludge Factors(and CPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** Physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition process parameter

Review on regulation of MnS in non-qquenched and tempered steel

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Journal of Iron and Steel Research International 2024年第4期31卷 779-789页

作者： Guo-xing Qiu Qing Du Feng Lu De-jun Miao Yong-kun Yang Xiao-ming Li School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina Laigang Technique Center Shandong Iron and Steel Group Co.Ltd.Jinan 271104ShandongChina

An overview of the current research status and control methods of MnS in non-quenched and tempered steel was *** a low-melting plastic inclusion,the morphology and distribution of MnS were influenced by various production ***,control of MnS is a systematic problem that must be integrated into the entire production *** on the production process,the factors affecting the morphology and distribution of MnS in steel were *** effects of oxygen activity,manganese,sulfur,and some alloys on MnS inclusion precipitation were summarized,mainly including MnS modification treatment and oxygen-sulfide composite precipitation *** is believed that MnS precipitates during the solidification process of steel,and controlling the solidification cooling rate could effectively regulate the size and morphology of MnS,avoiding the precipitation of ***,by changing the deformation rate,deformation amount,deformation temperature during the hot deformation process,and heating time and temperature during heat treatment,the distribution and morphology of MnS could be *** the fine control of the above process parameters,the number of II-MnS in steel could be effectively reduced,and their morphology could be improved,thereby enhancing the performance of non-quenched and tempered steel and promoting its wider ***,applying laboratory research results to industrial production is an important direction for future research efforts in this field.

关键词： MnS Non-quenched and tempered steel Control technology process parameter Morphology Distribution

Numerical analysis on the effect of process parameters on deposition geometry in wire arc additive manufacturing

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Plasma Science and Technology 2022年第4期24卷 1-12页

作者： Shilong FAN Fei YANG Xiaonan ZHU Zhaowei DIAO Lin CHEN Mingzhe RONG State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi'an Jiaotong UniversityXi'an 710049People's Republic of China

Here we develop a two-dimensional numerical model of wire and arc additive manufacturing(WAAM)to determine the relationship between process parameters and deposition geometry,and to reveal the influence mechanism of process parameters on deposition *** the predictive results,a higher wire feed rate matched with a higher current could generate a larger and hotter droplet,and thus transfer more thermal and kinetic energy into melt pool,which results in a wider and lower deposited layer with deeper ***,a higher preheat temperature could enlarge melt pool volume and thus enhance heat and mass convection along both axial and radial directions,which gives rise to a wider and higher deposited layer with deeper *** findings offer theoretical guidelines for the acquirement of acceptable deposition shape and optimal deposition quality through adjusting process parameters in fabricating WAAM components.

关键词： additive manufacturing arc plasma process parameter deposition geometry numerical analysis

Effect of process parameters on dry centrifugal granulation of molten slag by a rotary disk atomizer

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Journal of Iron and Steel Research International 2021年第3期28卷 263-271页

作者： Ri-jin Cheng Hua Zhang Yang Li Qing Fang Bao Wang Hong-wei Ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Technical Center HBIS Group Hansteel CompanyHandan056001HebeiChina

Dry centrifugal granulation(DCG)experiments for blast furnace slag(BFS)were performed by means of a rotary disk atomizer since water quenching method can create a series of *** results showed that the DCG method can granulate the BFS,but the results are easily affected by the slag flow rate,disk rotating speed,disk radius,disk material and slag falling *** granulating parameters with an excessive flow rate,low rotating speed,SiN–SiC disk,stainless steel disk and low slag falling height are detrimental to the granulation *** most suitable parameters for granulation are a slag flow rate of 5.1×10^(−5) m^(3)/s,a disk rotating speed of 1500–2300 r/min,a slag falling height of 0.8 m and a smooth graphitic disk with the radius of 0.1 *** the absence of an off-center flow,the overall best granulating effect produces round particles with mean diameter of 3.43 mm without creating slag *** vitreous content of the BFS particles granulated by graphite disks is 92%,which meets the requirements of cement raw *** Bond work index of dry granulated BFS is 18.4 kWh/t,and the grindability of dry granulated slag and water-quenched slag is similar.

关键词： Blast furnace slag Centrifugal granulation process parameter Disk property Grindability Vitreous content

Influence of process parameters on interracial tensile strength of crosswedge rolling of 42CrMo/Q235 laminated shafts

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Journal of Iron and Steel Research International 2018年第10期25卷 1003-1009页

作者： Wen-fei Peng Chao Yan Xiao Zhang Xue-dao Shu Guang-xing Huang Dong-ming Xu Zhejiang Provincial Key Lab of Part Rolling Technology Ningbo University Ningbo 315211 Zhejiang China Faculty of Mechanical Engineering and Mechanics NingboUniversity Ningbo 315211 Zhejiang China

Through rolling experiments and interfacial tensile strength tests of cross-wedge rolled laminated shafts of 42CrMo/Q235 composites, the influence of process parameters, including forming angle, spreading angle, area reduction, rolling temperature and core material diameter on the interfacial shear strength was analyzed. The results show that the sequence of process parameters in order of greatest influence on interfacial tensile strength was rolling temperature, area reduction, core material diameter, forming angle and spreading angle. At the interface of the combined materials, tensile strength decreased as forming angle and spreading angle increased, whereas the tensile strength first increased and then decreased as area reduction, rolling temperature and core material diameter increased.

关键词： Laminated shaft process parameter Interfacial tensile strength Cross-wedge rolling

Experimental Research on Effects of process parameters on Servo Scanning 3D Micro Electrical Discharge Machining

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 114-121页

作者： TONG Hao LI Yong HU Manhong State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

Servo scanning 3D micro electrical discharge machining (3D SSMEDM) is a novel and effective method in fabricating complex 3D micro structures with high aspect ratio on conducting materials. In 3D SSMEDM process, the axial wear of tool electrode can be compensated automatically by servo-keeping discharge gap, instead of the traditional methods that depend on experiential models or intermittent compensation. However, the effects of process parameters on 3D SSMEDM have not been reported up until now. In this study, the emphasis is laid on the effects of pulse duration, peak current, machining polarity, track style, track overlap, and scanning velocity on the 3D SSMEDM performances of machining efficiency, processing status, and surface accuracy. A series of experiments were carried out by machining a micro-rectangle cavity (900 μm×600 μm) on doped silicon. The experimental results were obtained as follows. Peak current plays a main role in machining efficiency and surface accuracy. Pulse duration affects obviously the stability of discharge state. The material removal rate of cathode processing is about 3/5 of that of anode processing. Compared with direction-parallel path, contour-parallel path is better in counteracting the lateral wear of tool electrode end. Scanning velocity should be selected moderately to avoid electric arc and short. Track overlap should be slightly less than the radius of tool electrode. In addition, a typical 3D micro structure of eye shape was machined based on the optimized process parameters. These results are beneficial to improve machining stability, accuracy, and efficiency in 3D SSMEDM.

关键词： micro electrical discharge machining(micro EDM) servo scanning machining 3D micro-structure process parameter

Effects of process parameters on the Temperature Field in Ti-6Al-4V Alloy Blade Precision Forging process

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Journal of Materials Science & Technology 2006年第4期22卷 473-477页

作者： Yuli LIU He YANG Tao GAO Mei ZHAN College of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

Blade precision forging is a high temperature and large plastic deformation process. process parameters have a great effect on temperature distribution in billet, so in this paper, by taking a Ti-6Al-4V alloy blade with a tenon as an object, the influence of process parameters on the temperature distribution in precision forging process was investigated using 3D coupled thermo-mechanical FEM （finite element method） code developed by the authors. The results obtained illustrate that：（1） the gradient of temperature distribution increases with increasing the deformation degree; （2） with increasing the initial temperature of the billet, the zones of high temperature become larger, and the gradient of temperature distribution hardly has any increase; （3） friction factors have little effect on the distribution of temperature field; （4） with increasing upper die velocity, temperature of the billet increases while the temperature gradient in billet decreases. The results are helpful to the design and optimization of the process parameters in precision forging process of Ti-alloy blade.

关键词： Ti-alloy blade Precision forging process parameter Temperature field Finite element method (FEM)

Influence of process parameters on hybrid forming of aluminum sheet

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Transactions of Nonferrous Metals Society of China 2001年第6期11卷 879-883页

作者：张新明陈明安中南大学材料科学与工程系湖南长沙 410083

The influences of the plastic melt pressure and its distribution from the gate to the end of the mold, and of the friction coefficient between the sheet flange and the mold on forming process of the aluminum sheet have been investigated by Finite Element Method. It was shown that further deformation is mainly concentrated on metal sheet around the root corner of the mold, and that two highly strained zones with the severest thickness reduction are formed when the plastic melt pressure increased from 30?MPa to 50?MPa. The deformation of the sheet flange decreased and biaxial tension in plane of the sheet in the mold increased with increase of the friction coefficient. The non uniform distribution of the plastic melt pressure had negligible influence on forming process of the sheet.

关键词： sheet metal forming injection molding process parameter finite element method (FEM) aluminum sheet

Mesoscopic-Scale Numerical Investigation Including the Influence of process parameters on LPBF Multi-Layer Multi-Path Formation

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Computer Modeling in Engineering & Sciences 2021年第1期126卷 5-23页

作者： Liu Cao Institute for Systems Rheology School of Mechanical and Electrical EngineeringGuangzhou UniversityGuangzhou Higher Education Mega CenterGuangzhou510006China

As a typical laser additive manufacturing technology,laser powder bed fusion(LPBF)has achieved demonstration applications in aerospace,biomedical and other ***,how to select process parameters quickly and reasonably is still themain concern of LPBF *** order to quantitatively analyze the influence of different process parameters(laser power,scanning speed,hatch space and layer thickness)on the LPBF process,the multilayer and multi-path forming process of LPBF was predicted based on the open-source discrete element method framework Yade and the open-source finite volume method framework *** on the design of experiments method,a four-factor three-level orthogonal test scheme was designed,and the porosity and surface roughness data of each calculation scheme were *** analyzing the orthogonal test data,it was found that as the laser power increased,the porosity decreased,and as the scanning speed,hatch space,and layer thickness increased,the porosity *** addition,the influence of laser power and scanning speed on surface roughness showed a trend of decreasing first and then increasing,while the influence of scanning distance and layer thickness on surface roughness showed amonotonous increasing *** order of the influence of each process parameter on porosity was:scanning speed>laying thickness>laser power>hatch space,and the order of the influence of each process parameter on surface roughness was:hatch space>layer thickness>laser power>scanning *** the porosity of the part is most sensitive to scanning speed,and the surface roughness is the most sensitive to hatch *** above conclusions are expected to provide process control basis for actual LPBF production of the 316L stainless steel alloy.

关键词： Laser powder bed fusion process parameter porosity surface roughness orthogonal test method numerical simulation