Study on the Cavity Defects of Low-Pressure Lost Foam Casting for Magnesium Alloy

2012 ◽  
Vol 201-202 ◽  
pp. 1151-1154
Author(s):  
Ji Qiang Li ◽  
Zhong Zhao ◽  
Zhi Xin Jia ◽  
Yun Wei Xu ◽  
Zhi Yuan Liu
Keyword(s):  
Magnesium Alloy ◽  
Low Pressure ◽  
Lost Foam Casting ◽  
Cavity Surface ◽  
Metal Mold ◽  
Pouring Temperature ◽  
Chemical Constitution ◽  
Energy Spectrometer ◽  
Lost Foam ◽  
Slag Entrapment

Cavity defects of low-pressure lost foam casting (LP-LFC) for magnesium alloy were investigated by using ladder samples and claviform samples.The physical feature of typical cavity defects of LP-LFC for magnesium castings had been tested by optical microscopy and scanning electron microscopy. And the chemical constitution of cavity surface was also tseted by energy spectrometer. The result indicated that the cluster cavity defects were formed with the application of higher vacuum at the metal-mold interface, which caused the liquid-EPS residue in the castings. Some irregular shape cavity defects were caused by slag entrapment or coating slough. These cavity defects could be avoided through reducing pouring temperature, filling velocity and vacuum level, improving the permeability of coating.

Determination of Optimal Temperature for Defect-Free Casting of Aluminium in the LP-LFC Process

2011 ◽  
Vol 101-102 ◽  
pp. 934-937
Author(s):  
Ji Qiang Li ◽  
Zhong Zhao ◽  
Zi Tian Fan ◽  
Zhi Xin Jia ◽  
Wen Liu ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Aluminium Alloys ◽  
Low Pressure ◽  
Experimental Results ◽  
Metal Temperature ◽  
Lost Foam Casting ◽  
Optimal Temperature ◽  
Pouring Temperature ◽  
Lost Foam

Fluidity of ZL101 aluminium alloys in the low-pressure lost foam casting (LP-LFC) process has been investigated by altering various temperature variables. The experimental results indicate that the LP-LFC process had fine fluidity, and the pouring temperature was lower than conventional lost foam casting. The effect of the metal temperature on the fluidity is marginal in the LP-LFC process. Excessive pouring temperature not only aggrandizes energy consumption but also deteriorates porosity defect. The success of casting cooling fin demonstrates the advantages of LP-EPC process in producing high-complicated castings.

Lost Foam Casting of Hydroturbine Blades Based on CAE

2011 ◽  
Vol 71-78 ◽  
pp. 694-697
Author(s):  
Jian Zhou ◽  
Li Jun Li ◽  
Jian Wen Yi ◽  
Ming Yang
Keyword(s):  
Model Material ◽  
Raw Material ◽  
Lost Foam Casting ◽  
Polystyrene Foam ◽  
Pouring Temperature ◽  
Fireproof Coating ◽  
Lost Foam ◽  
Foam Plastics ◽  
Lower Carbon ◽  
Carbon Martensite

The article studies the method which hydroturbine part is manufactured by lost foam casting for obtaining higher quality product.The lost model material is polystyrene foam plastics,the EPS diameters are selected in 0.5-0.76mm,the casting raw material is lower carbon martensite stainless steel(ZG06Cr13Ni4Mo).The style of open pouring system is adopted, ∑Fin-gate：∑Fcross-gate：∑Fdown-sprue=1：1.1：1.2, fireproof coating is mixed and coated,square sand box is used. The pouring temperature of liquid is 1600-1650°C.If the technology is strictly according to the design,good quality casting can be gotten.

scholarly journals Investigation of temperature, degree of vacuum, pattern coating thickness effects on mold filling in lost foam casting (LFC) process of A356 alloy

2015 ◽  
Vol 18 (2) ◽  
pp. 94-103
Author(s):  
Ha Ngoc Nguyen ◽  
Phong Quoc Le ◽  
Tri Nhat Nguyen ◽  
Hoai Dinh Lai
Keyword(s):  
Coating Thickness ◽  
A356 Alloy ◽  
Mold Filling ◽  
Complex Model ◽  
Production Costs ◽  
Lost Foam Casting ◽  
Pouring Temperature ◽  
Casting Technique ◽  
Lost Foam ◽  
Dipping Time

Lost foam casting (LFC) process with outstanding advantages has been known as a new casting technique in foundry engineering. Especially, the operation restricts errors of a mould because of using expanded patterns without parting line being appropriate for the complex model. Great interest in this technology of the casting manufacturers is mainly lower, compared with the traditional process, investment outlays and production costs. The use of unbounded sand also reduces its treatment cost, more friendly and simple with the environment. The study examines the simultaneous effects of pouring temperature, degree of vacuum, coating thickness (through dipping time) on mold filling in LFC. A356 aluminum alloy is used in this study. By using a full two-level factorial design of experimental technique to identify the significant manufacturing factors affecting the mold filling. Results of this investigation indicated that increasing pouring temperature, degree of vacuum and decreasing dipping time obtain casting with higher filling rate.

DOE Analysis of the Influence of Sand Size and Pouring Temperature on Porosity in LFC

2011 ◽  
Vol 121-126 ◽  
pp. 2661-2665
Author(s):  
S. Izman ◽  
Amirreza Shayganpour ◽  
M.H. Idris ◽  
Hassan Jafari
Keyword(s):  
Cast Alloy ◽  
Experimental Investigations ◽  
Lost Foam Casting ◽  
Thin Wall ◽  
Pouring Temperature ◽  
New Process ◽  
Casting Porosity ◽  
Lost Foam ◽  
Significant Factors ◽  
Sand Size

Lost foam casting is a relatively new process in commercial terms and is widely used to produce defect free castings owing to its advantages like producing complex shape and acceptable surface finish. In the present research, experimental investigations in lost foam casting of aluminium-silicon cast alloy, LM6, were conducted. The main objective of the study was to evaluate the effect of different sand sizes and pouring temperatures on the porosity of thin-wall castings. A stepped pattern was used in the study and the focus of the investigations was at the thinnest 3 mm section. A full 2-level factorial design experimental technique was employed to plan the experiment and subsequently identify the significant factors which affect the casting porosity. The result shows that increasing in the pouring temperature decreases the porosity in the thin-wall section of casting. Finer sand size is more favourable than coarse size for LFC mould making process.

Influence of Vibration on the Heat Transfer of Lost Foam Casting Filling

2011 ◽  
Vol 418-420 ◽  
pp. 1618-1621 ◽  
Author(s):  
Zhong Zhao ◽  
Zi Tian Fan
Keyword(s):  
Heat Transfer ◽  
Magnesium Alloy ◽  
Molten Metal ◽  
A356 Alloy ◽  
Vibration Energy ◽  
Lost Foam Casting ◽  
Flow Front ◽  
Filling Time ◽  
Lost Foam ◽  
Filling Capacity

The vibration is superimposed to the filling process of aluminum and magnesium alloy in lost foam casting, and the flow lengths and the molten metal temperatures of the flow front are collected, and they compared with no-vibration. The results show that the vibration can significantly improve the filling capacity of the aluminum alloy, magnesium alloy in lost foam casting. Compared to the samples without vibration, the flow lengths of A356 alloy with vibration in lost foam casting increased by 33% and that of AZ91D alloy increased by 15%.The heat transfer of molten metal on the flow front was analyzed, and it indicates that the vibration energy extends the filling time of the molten metal on the flow front in lost foam casting.

Sign in / Sign up

Export Citation Format

Share Document