Effect of whisker orientation on the stress corrosion cracking behavior of alumina borate whisker reinforced pure Al composite

doi:10.1016/S0167-577X(02)00569-4

Materials Letters

Volume 56, Issue 5, November 2002, Pages 642-646

https://doi.org/10.1016/S0167-577X(02)00569-4 Get rights and content

Abstract

Stress corrosion cracking (SCC) behavior of as-extruded alumina borate whisker (Al₁₈B₄O₃₃)w reinforced pure aluminum composite in 3.5%NaCl solution was investigated using double cantilever beam (DCB) method. The effect of whisker orientation on the stress corrosion cracking behavior of the composite after extrusion was examined. The results indicated that the crack propagated easily along the interface between whisker and matrix in the composite. The whisker orientation plays an important role in stress corrosion cracking of the composite after extrusion.

Section snippets

Instruction

The aluminum matrix composite have received considerable attention because of their superior properties as compared to most conventional materials in terms of specific strength, stiffness, and wear resistance in addition to a service temperature capability [1]. Therefore, aluminum matrix composites are expected to be widely used in a variety of applications, such as connecting rod, automotive drive shaft, cylinder liner and brake rotor [2], [3], [4]. Nevertheless, the composite can be affected

Experimental

The composite used in this study was fabricated by squeeze casting. The matrix alloy is pure aluminum. The reinforcement is alumina borate whisker, the volume fraction of the whisker is about 20%. The preheating temperature of the mold and preform was about 500 °C, and the melting pure aluminum was 750–800 °C, die pressure was about 100 MPa. The composite microstructure is shown in Fig. 1. It can be seen that the whisker is uniformly distributed in the composite.

As-cast composite was extruded,

Results and discussion

Fig. 3 shows the morphology of whisker distribution in the as-extruded composite. It can be seen in the whisker orientation arrangement.

The observation indicated that there was no stress corrosion cracking in specimen #1 when it was immersed in 3.5%NaCl solution for 1 month, but the other specimens did stress-corrode in 3.5%NaCl solution.

Fig. 4 shows the relationship between the crack propagation length and the corrosion time for specimen #2. At the initial stage of corrosion, the crack length

Conclusions

1.
Pits formed in front of the crack tip lead to crack blunting and decrease in crack propagation rate.
2.
No stress corrosion cracking in the specimen with the applied stress is parallel to the extrusion direction in 3.5%NaCl solution for extruded Al₁₈B₄O₃₃w/p-Al composite.
3.
The sensibility of SCC of the specimen with the applied stress vertical to the extrusion direction is the highest for the Al₁₈B₄O₃₃w/p-Al composite.
4.
Interface between the whisker and matrix is the main path for propagation of cracks.

Acknowledgements

This work is supported by the Scientific Research Foundation of Harbin Institute of Technology, Project No. ACQQ18000058.

References (7)

S. Ho et al.
Three-dimensional modeling of thermal residual stresses and mechanical behavior of cast SiC/Al particulate composites
Acta Metall. Mater.
(1994)
B.-C. Ko et al.
The effect aging treatment on the microstructure and mechanical properties of AA2124 composites reinforced with both SiC whisker and SiC particle
Comput. Sci. Technol.
(1999)
K.S. Ravichandran
A simple model of deformation behavior of two phase composites
Acta Metall. Mater.
(1994)

There are more references available in the full text version of this article.

Cited by (7)

Growth behavior of aluminum borate whiskers on zirconia toughened alumina (ZTA) particle surface
2020, Ceramics International
Citation Excerpt :
In addition, it has been reported that the application of Al18B4O33 whiskers to ZK60 magnesium alloy improves the behaviour of the composite [14]. Moreover, Hu has reported that during stress corrosion, cracks in whisker-reinforced aluminium matrix composites mainly propagate along the grain boundaries, and the whiskers hinder the crack propagation [15]. It is common to study the growth of whiskers on the surface of Al2O3 or ZTA ceramics.
In this work, B₄C-covered zirconia-toughened alumina (ZTA) particles are prepared and oxidised at 1050 °C for different times (0, 2, 4, and 8 h) in air. The X-ray diffraction and electron probe micro-analysis results show that the covering layer is mainly composed of oxide B₂O₃ intermetallics, residual B₄C particles, and Al₁₈B₄O₃₃ whiskers. The scanning electron microscopy results show that the growth of Al₁₈B₄O₃₃ whiskers on the ZTA particles enhances with increasing heat preservation time; the optimum holding time is determined to be 8 h Al₂O₃ in the ZTA particles diffuse into the covering layer and combine with B₂O₃ to form Al₁₈B₄O₃₃ whiskers; the Al₁₈B₄O₃₃ whiskers grow via the liquid-solid mechanism.
Stress corrosion cracking (SCC) of aluminium alloys
2011, Stress corrosion cracking: Theory and practice
The stress corrosion cracking (SCC) behaviour of aluminium alloys has been studied for the past five decades and is still a research area of high interest due to the demand for higher strength aluminium alloys for fuel saving. This chapter brings out the general understanding of the SCC mechanism(s) and the critical metallurgical issues affecting the SCC behaviour of aluminium alloys. The developments made so far with regard to alloying and heat treatment of aluminium alloys for high SCC resistance are discussed. An overview of the available literature on the SCC of aluminium alloy weldments and aluminium alloy metal matrix composites is also presented.
Effect of annealing treatment on microstructure and tensile strength of alumina borate whisker-reinforced Al-Mg composite
2006, Materials Science and Engineering: A
The microstructures of alumina borate whisker reinforced Al–Mg composite, subjected to different annealing treatment, was studied using transmission electron microscopy. The characteristics of interfacial phases and the dislocation states in the matrix were investigated. The results indicated that the interfacial reaction between the whisker and the matrix in the composite cannot occur at 320 °C. The amount of interfacial phases reduces with the increase in annealing treatment time. The precipitation of Al₈Mg₅ at the whisker/matrix interface can dissolve into the matrix aluminum during annealing treatment. The dislocation states and the interfacial precipitation affect the tensile strength of the composite obviously, and the suitable annealing treatment process can be found for the ultimate tensile strength.
Effect of interfacial reaction on corrosion behavior of alumina borate whisker reinforced 6061Al composite
2004, Materials Science and Engineering: A
The effect of interfacial reaction on the corrosion behaviors of alumina borate whisker (Al₁₈B₄O₃₃w) reinforced aluminum composite has been analyzed in 3.5% NaCl solution at room temperature.
The localized corrosion susceptibilities and the stress corrosion cracking behaviors of the composite for each heat treatment were examined by measurement through the cyclic potentiodynamic polarization and double cantilever beam tests.
It was found that the degrees of interfacial reaction increase with solution treatment time, and the various degrees of the interfacial reaction led to the difference of composition distribution near the interface between whisker and matrix in the composite. The interfacial reaction plays an important role in the electrochemical corrosion behaviors and stress corrosion cracking behaviors of the composite.
Research on the Process and Mechanism of Reactive Air Brazing of Al<inf>2</inf>O<inf>3</inf> Ceramics with AgCu28-B<inf>2</inf>O<inf>3</inf> Filler
2023, Jixie Gongcheng Xuebao/Journal of Mechanical Engineering
Corrosion Behaviors of 5A06 Aluminum Alloy Sheet Under Stress Loading in Brine Solution
2018, Cailiao Gongcheng/Journal of Materials Engineering

View all citing articles on Scopus

View full text