Study on Mechanical Properties of Lost Foam Pattern in Machining

2021 ◽  
Vol 904 ◽  
pp. 148-153
Author(s):  
Hong Qi Luo ◽  
Xia Liu ◽  
Po Wang
Keyword(s):  
Mechanical Properties ◽  
Manufacturing Industry ◽  
Rapid Development ◽  
Numerical Control ◽  
Processing Technology ◽  
Lost Foam Casting ◽  
Mechanical Equipment ◽  
Theoretical Support ◽  
Foam Pattern ◽  
Lost Foam

Lost foam casting has special requirements on the process performance of molding machinery, and the processing technology of Lost foam casting pattern is one of the core and key technologies of Lost foam casting. The research status of lost foam pattern and the safety problems existing in the process of lost foam casting were analyzed. The mechanical properties of lost foam pattern and its mechanical property model were studied, which provided theoretical support for the research of numerical control processing and safe casting of lost foam pattern. The development of Lost foam casting pattern NC processing technology is conducive to the use of information technology, digital technology to enhance the technological progress of traditional industries, promote the clean production of Lost foam casting, realize energy saving and emission reduction, and promote the rapid development of mechanical equipment manufacturing industry.

scholarly journals Influence of Pattern Coating Thickness on Porosity and Mechanical Properties of Lost Foam Casting of Al-Si (LM6) Alloy

2013 ◽  
Vol 300-301 ◽  
pp. 1281-1284
Author(s):  
Shamsuddin Sulaiman ◽  
M.K.A.M. Ariffin ◽  
S.H. Tang ◽  
A. Saleh
Keyword(s):  
Mechanical Properties ◽  
Molten Metal ◽  
Coating Thickness ◽  
Air Entrainment ◽  
Expanded Polystyrene ◽  
Lost Foam Casting ◽  
Polystyrene Foam ◽  
Porosity Distribution ◽  
Foam Pattern ◽  
Lost Foam

The combination of Aluminum alloy with lost foam casting (LFC) process is best applied in automotive industry to replace steel components in order to achieve light weight components for reducing fuel consumption and to protect the environment. The LFC process involves process parameters such as the degree of vacuum, foam degradation, expanded polystyrene (EPS) foam density, permeability of foam pattern coatings, pouring temperature, filling velocity, cooling rate, and pressure. The effect of polystyrene foam pattern coating thickness on the porosity and mechanical properties of Aluminum Al-Si LM6 alloy were evaluated experimentally. The coating thickness was controlled by slurry viscosity at range between 18sec to 20sec using Zahn viscosity cup No.5 and the foam pattern was coated up to fifth layer. Aluminum Al-Si (LM6) molten metal was poured into expandable mould and castings were examined to determine porosity distribution, mechanical properties and microscopic observation. Results from X-ray testing reveal the porosity distribution on Aluminum Al-Si LM6 castings is greater at thicker foam pattern coating sample. Meanwhile, the tensile strength of casting decreases when foam pattern coating thickness increases. Microscope observation portray the present of porosity on the casting which shows more gas defects present at thicker foam pattern coating sample. The source of porosity in LFC process is due to air entrainment or the entraining gases from polystyrene foam decomposition during pouring of molten metal. As a conclusion, mechanical strength has inverse relationship with porosity.

Thermal Analysis during Solidification of Mg-4%.wtAl Alloy during Lost Foam Casting Process

2011 ◽  
Vol 686 ◽  
pp. 371-377 ◽  
Author(s):  
D.H. Hou ◽  
S.M. Liang ◽  
Rong Shi Chen ◽  
En Hou Han ◽  
C. Dong
Keyword(s):  
Thermal Analysis ◽  
Grain Size ◽  
Casting Process ◽  
Expanded Polystyrene ◽  
Solidification Structure ◽  
Lost Foam Casting ◽  
Dendrite Morphology ◽  
Dendrite Coherency ◽  
Foam Pattern ◽  
Lost Foam

The lost foam casting (LFC) process utilizes the expanded polystyrene (EPS) foam pattern for the production of metallic components. The thermal degradation of the foam pattern has a significant effect on microstructure of the component. Dendrite coherency is important for the determination of the formation of the solidification structure and cast ability of alloys. The effects of the dendrite coherency on grain size in Mg-4Al alloy have been studied using the two-thermocouple thermal analysis technique in the solidified sample. The results also indicate that the grain size increases with the temperature interval between liquids (TN) and dendrite coherency point (TDCP), The solid fraction at DCP (fsDCP) expressed in percent strongly dependents on the dendrite morphology during solidification.

scholarly journals An Empirical Analysis on Why People Run Away from In-Feed Ads under Manufacturing Industry Innovation

CONVERTER ◽  
2021 ◽  
pp. 88-103
Author(s):  
Xiaobo Tao, Ziniu Jin
Keyword(s):  
Avoidance Behavior ◽  
Manufacturing Industry ◽  
Rapid Development ◽  
Mobile Internet ◽  
Moderating Effects ◽  
Theoretical Support ◽  
Perceived Relevance ◽  
And Coping ◽  
Marketing Methods ◽  
Study Designs

Thanks to the innovation in manufacturing industry,the rapid development ofdigital technologies such as mobile Internet and social media enables the appearance of up-to-date intelligent marketing methods. As one of them, In-Feed advertising becoming a fashionable approach due to its precise positioning and growing market share, problems such as loss of privacy and lack of trust arise which promote the avoidance behavior of consumer. Based on these facts, our study designs three experiments to explore the mechanism between the In-Feed advertising and the avoidance behavior of consumer. Furthermore, in order to give instructions on enhancing the communication effect of In-Feed ads, we tries to clarify the boundary conditions of consumers processing ads information. Experiment 1 examines the moderating effects of ad reviews between perceived relevance, threat appraisal and coping appraisal; Experiments 2 and 3 respectively examine the moderating effects of the connection strength and interaction frequency between consumers and ad-likers between the above variables. These three experimental results provide theoretical support and practical guidance for intelligent digital marketing and advertising.

Measurement of Kinetic Zone Temperature and Heat Transfer Coefficient in the Lost Foam Casting Process

2004 ◽  
Author(s):  
X. J. Liu ◽  
S. H. Bhavnani ◽  
R. A. Overfelt
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Casting Process ◽  
Lost Foam Casting ◽  
Foam Pattern ◽  
Lost Foam ◽  
The Heat Transfer Coefficient ◽  
Zone Temperature

A thermometric technique has been developed to study the thermal characteristics of the foam-metal interaction in the lost foam casting process. A cylindrical foam pattern and heated steel block have been used to estimate the endothermic losses associated with the thermal degradation of the expanded polystyrene at the metal front. Thermocouple readings have been analyzed to determine the temperature of the kinetic zone between the advancing metal front and the receding foam pattern. The heat transfer coefficient between the metal front and the foam pattern has been calculated from the thermal data at the simulated metal front. The results confirmed that the endothermic degradation of the polystyrene pattern at the metal front introduced a steep thermal gradient in the metal and a consistently increasing heat flux. It is found that the heat transfer coefficient, initially 150 W/m2·K increases to 220 ~ 300 W/m2·K during the process. Foam density has marginal effect on the heat flux and heat transfer coefficient, whereas the increase of simulated metal front velocity enhances the heat transfer at the metal front. The kinetic zone temperature is measured to be in the range of 150 to 290°C with an average of 200°C and a gaseous gap size of 1 to 4 cm.

Effect of Superheat Melt Treatment on Microstructure and Mechanical Properties of Aluminum Alloys Produced by Lost Foam Casting

2018 ◽  
Vol 284 ◽  
pp. 593-597 ◽  
Author(s):  
Vladislav Deev ◽  
Evgeny Prusov ◽  
K. Ponomareva
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloys ◽  
Technology Implementation ◽  
Isothermal Holding ◽  
Lost Foam Casting ◽  
Resource Saving ◽  
Fine Grained ◽  
Aluminum Castings ◽  
Temperature State ◽  
Lost Foam

The resource-saving technology for producing of thin-walled castings from A356.1, A413.1 and A360.0 aluminum alloys by the lost foam casting method, as well as the results of this technology implementation in production conditions are considered in the paper. The technology involves thermo-speed treatment of the melt with the predominance of secondary materials in charge (85...90 wt.%), including isothermal holding and subsequent rapid cooling of the melt for fixation the high-temperature state. It is shown that the use of thermo-speed treatment promotes the production of aluminum castings with fine-grained microstructure and the enhanced level of mechanical properties without the addition of costly modifying additives, and makes it possible to use an increased amount of secondary charge materials during smelting.

Microstructure and Mechanical Properties of Lost Foam Casting AZ91D Alloy Produced with Mechanical Vibration

2011 ◽  
Vol 213 ◽  
pp. 5-8 ◽  
Author(s):  
Ji Qiang Li ◽  
Zi Tian Fan ◽  
Xuan Pu Dong ◽  
Wen Liu ◽  
Xianyi Li
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Strong Influence ◽  
Mechanical Vibration ◽  
Lost Foam Casting ◽  
Az91d Alloy ◽  
Az91d Magnesium Alloy ◽  
Coarse Microstructure ◽  
Alloy Increase ◽  
Lost Foam

Mechanical vibration was introduced into the solidification in order to overcome the defects of coarse microstructure and low mechanical properties of the AZ91D magnesium alloy via lost foam casting（LFC）. The microstructure with fine uniform dendrite grains were achieved with mechanical vibration, which was mainly attributed to the cavitation and the melts flow induced by the mechanical vibration. The mechanical vibration has strong influence on the mechanical properties of AZ91D alloy. With application of mechanical vibration, the ultimate tensile strength and elongation of the AZ91D alloy increase 23% and 26%, resepectively.

Mechanical Properties of A6063/SiC Composites Produced Using the Lost Foam Casting Process

2012 ◽  
Vol 54 (3) ◽  
pp. 189-192
Author(s):  
Kerem Altug Güler ◽  
Alptekin Kisasoz ◽  
Caglar Yuksel ◽  
Ahmet Karaaslan
Keyword(s):  
Mechanical Properties ◽  
Casting Process ◽  
Lost Foam Casting ◽  
Sic Composites ◽  
Lost Foam

Numerical Modeling of EPS Foam Decomposition in the Lost Foam Casting Process

2005 ◽  
Author(s):  
X. J. Liu ◽  
S. H. Bhavnani ◽  
R. A. Overfelt
Keyword(s):  
Heat Transfer ◽  
Process Parameters ◽  
Experimental Studies ◽  
Casting Process ◽  
Mold Filling ◽  
Lost Foam Casting ◽  
Interfacial Heat Transfer Coefficient ◽  
Filling Process ◽  
Foam Pattern ◽  
Lost Foam

The importance of smooth mold filling in the lost foam casting process has been recognized for a long time. The more uniform the filling process, the better the quality of the casting products that are produced. Successful computer simulations can help reduce the number of trials and cut down the lead time in the design of new casting products by better understanding the complex mechanisms and interplay of different process parameters in the mold filling process. In this study, a computational fluid dynamics (CFD) model has been developed to simulate the fluid flow of molten aluminum and the heat transfer involved at the interfacial gap between the metal and the expanded polystyrene (EPS) foam pattern. The commercial code FLOW-3D was used because it can track the front of the molten metal by a Volume of Fluid (VOF) method and allow complicated parts to be modeled by the Fractional Area/Volume Ratios (FAVOR) method. The code was modified to include the effects of varying interfacial heat transfer coefficient based on gaseous gap pressure which is related to foam degradation and coating permeability. The modification was validated against experimental studies and the comparison showed better agreement than the basic model. Process parameters such as initial metal temperature, foam pattern property, and gating system were investigated. The defect prediction model was also used to study the dependence of defect formation on the process variables.

Theoretical research on sector oil-pads’ mechanical property in hydrostatic thrust bearing based on constant flow

2017 ◽  
Vol 69 (4) ◽  
pp. 491-506 ◽  
Author(s):  
Xibing Li ◽  
Tian Cheng ◽  
Ming Li ◽  
Mingjian Li ◽  
Ruren Wu ◽  
...  
Keyword(s):  
Pressure Difference ◽  
Thrust Bearing ◽  
Rapid Development ◽  
Numerical Control ◽  
Theoretical Research ◽  
Mechanical Equipment ◽  
Content Type ◽  
Large Size ◽  
Lubrication Performance ◽  
Oil Flow

Purpose The purpose of this study with the rapid development of the heavy/large mechanical equipment, the heavy computer numerical control (CNC) vertical lathe has become the ideal processing equipment for the parts of those mechanical equipments. The main factor which affects the machining quality and efficiency of heavy CNC vertical lathe is the mechanical properties of the hydrostatic thrust bearing. Design/methodology/approach This paper did the research based on the large size sector oil pad’s lubrication performance of the hydrostatic thrust bearing in the heavy/large equipments, establishing the lubrication performance distribution mathematical model of the velocity field, flow field, pressure field and so on, analyzing the bearing behavior of the large size sector oil pad. Findings The results show that the oil flow generated by the plate relative motion will be greater than that generated by the pressure difference in area B, with the rotational speed’s increasing of the hydrostatic thrust bearing, and the direction is opposite. The oil flow generated by the centrifugal force will be greater than that generated by the pressure difference in area C, with the rotational speed’s increasing of the hydrostatic thrust bearing, and the direction is opposite. When the rotational speed of the hydrostatic thrust bearing is too high, the friction heat will be not easy to be sent out. The bearing rotating speed should be lower than the comparatively smaller one of ω1 and ω2, which can help avoid the rise of too high temperature. Originality/value The research provides powerful theoretical foundation for practical application of the large size sector oil pad hydrostatic thrust bearing, its structure design and operating reliability, realizing the lubrication performance prediction of the large size hydrostatic thrust bearing.

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