Effect of Particle Size in Feedstock Properties in Micro Powder Injection Molding

The paper presents the result of an experimental investigation on the fabrication of Al/SiC composites with high volume fraction of SiC particles by pressure infiltration of liquid aluminum into preforms prepared by powder injection molding (PIM). To obtain the required high particle volume fraction, SiC powders with a bimodal particle size distribution were used. The influence of powder loading and particle size on the bending strength of the prepared composites has been investigated. It is demonstrated that pressure infiltration permits to achieve high relative densities for the composites (i.e. 98.8%). The microstructure studies revealed a uniform distribution of SiC particles in the composites without interface reactions between the particles and the aluminum matrix. The bending strength increases with increasing powder loading and decreasing particle size of the coarse powders in the bimodal powder system.

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The Role of Powder Particle Size Distribution in the Processability of Powder Injection Molding Compounds

International Journal of Polymer Analysis and Characterization ◽

10.1080/1023666x.2011.547047 ◽

2011 ◽

Vol 16 (2) ◽

pp. 141-151 ◽

Cited By ~ 10

Author(s):

B. Hausnerova ◽

T. Kitano ◽

I. Kuritka ◽

J. Prindis ◽

L. Marcanikova

Keyword(s):

Particle Size ◽

Injection Molding ◽

Particle Size Distribution ◽

Size Distribution ◽

Powder Particle ◽

Powder Injection Molding ◽

Powder Injection ◽

Powder Particle Size ◽

Molding Compounds

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Thermo-Physical Properties of SiCAl Composites with High Volume Fraction of Reinforcement Prepared by Combining Powder Injection Molding and Pressure Infiltration

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.1832 ◽

2011 ◽

Vol 239-242 ◽

pp. 1832-1837

Author(s):

Hao He ◽

Yi Min Li

Keyword(s):

Particle Size ◽

Injection Molding ◽

Physical Properties ◽

Volume Fraction ◽

High Volume ◽

Powder Injection Molding ◽

Powder Injection ◽

Pressure Infiltration ◽

Johnson Model ◽

Thermo Physical Properties

SiC/Al composites with high reinforcement content were fabricated by pressure infiltration of aluminum alloy into porous SiC preform obtained by powder injection molding using a bimodal powder mixture. The influence of powder loading and particle size on the thermo-physical properties of the prepared composites was investigated. The results indicate that the thermal conductivities (TC) increases and coefficients of thermal expansion (CTE) decreases with increasing powder loading and particle size of the coarse powders in the bimodal powder system. The TCs are below the estimated value based on Hasselman-Johnson model, mainly due to the residual pores and the irregular particle shape. The CTEs of the composites increase with increasing temperature from 100°C to 400°C, and the increasing rates vary at different temperature ranges. Deep cooling in liquid nitrogen is effective to bring dislocations in the matrix and thus reduces the CTEs.

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