銅粉末 成形體의 收縮異方性에 관하여

Abstract

銅系 분말 성형체의 소결시 수축이방성에 미치는 분말입도, 성형압 및 성형방법의 영향을 조사하고 소결 진행에 따르는 수축비의 거동을 조사하였다.

Cu-die 성형체의 경우 조대한 분말 성형체에서 소결이 진행됨에 따른 수축비는 성형압의 영향이 현저하였고 적은 성형압의 시료에서 보다 큰 수축비값을 보여 주었다.

등압성형체 및 Cu-Sn 성형체의 소결에서는 소결초기에 수축비에 미치는 성형압의 영향은 현저히 나타났으나 소결진행에 따라 보다 안정된 값을 보여 주었다.

소결시 성형압에 기인한 이방성응력 및 소결단계에 따른 조밀화, 재배열 과정의 기공의 형상학적 거동이 수축비에 미치는 영향을 논의하였다.

The anisotropic shrinkage during sintering in compacts made of Cu and Cu-Sn powders with irregular shape has been investigated as function of powder particle size, compaction sressure, compaction method and sintering time. The behavior of radial/axial(R/A) shrinkage throughout the sintering process has been studied.

In the case of coarser powder die compacts of copper, the R/A ratio was found to be strongly affected by the sintering process and the compacting pressure; e.g., the lower the compacting pressure was, the higher the R/A ratio was observed. The isostatic compacts and Cu-Sn powder compacts showed more stable value of R/A ratio. The influence of compacting pressure on R/A ratio for isostatic compacts was pronounced in the eary stage of sintering but become negligible in the late stage.

The possible morphological change of residual pores in the early and later stages of sintering, such as anisotropic and densification due to compaction pressure and rearrangement of particles, were discussed together with other factors to explain the phenomena.

The anisotropic shrinkage during sintering in compacts made of Cu and Cu-Sn powders with irregular shape has been investigated as function of powder particle size, compaction sressure, compaction method and sintering time. The behavior of radial/axial(R/A) shrinkage throughout the sintering process has been studied.

In the case of coarser powder die compacts of copper, the R/A ratio was found to be strongly affected by the sintering process and the compacting pressure; e.g., the lower the compacting pressure was, the higher the R/A ratio was observed. The isostatic compacts and Cu-Sn powder compacts showed more stable value of R/A ratio. The influence of compacting pressure on R/A ratio for isostatic compacts was pronounced in the eary stage of sintering but become negligible in the late stage.

The possible morphological change of residual pores in the early and later stages of sintering, such as anisotropic and densification due to compaction pressure and rearrangement of particles, were discussed together with other factors to explain the phenomena.