Assessment of AlN/Mg–8Al Composites Reinforced with In Situ and/or Ex Situ AlN Particles

Abstract

In this paper, 8.2AlN/Mg–8Al composites reinforced with in situ and/or ex situ AlN particles have been synthesized. The in situ-formed AlN particles are nano-sized, performing as particle chains. It has been clarified that the in situ AlN particles are more efficient than ex situ particles for the enhancement of mechanical properties. The in situ-prepared composite exhibits improved density, hardness and compressive strength compared to the ex situ ones. This work may be referred to for designing particle-reinforced Mg composites by various methods.

Progress in preparation of AlN-reinforced magnesium matrix composites: A review

“…Zhang et al [51] proposed that the following reactions may also occur in the molten Mg: (4) (5) Mg 2 Si for achieving proper performance of the (AlN+Mg 2 Si)/Mg composite. Gao et al [52] prepared in-situ AlN/Mg-8Al composites by using BN as solid nitrogen. Mg powder, Al powder and BN powder were firstly mixed proportionally and then cold-pressed to obtain preformed blocks.…”

“…7(c) and (d) reveals the presence of AlN chains on the shear surface. Gao et al [52] suggests that this distribution of chain-like AlN surrounds the Mg matrix and that the particle chains may be subjected to higher stresses or pile up more dislocations during loading [53,54] . The AlN-MMCs prepared by several in-situ techniques mentioned above are summarized in Table 4.…”

“…Fig. 7: TEM images and fracture morphology of in-situ AlN/Mg-8Al composites: (a) dark field image; (b) HRTEM image; (c) low magnification of shear fracture; (d) high magnification of shear fracture[52] …”

Farklı seramik kaplı Ti-6Al-4V alaşımının doğal frekansına konik açı ve sınır koşulunun etkisinin sonlu eleman analizi ile incelenmesi

“…During the modeling procedure, both beam and coating layer was created with different areas and then these areas were glued to each other to be able to define different material properties for the beam and coating layer. These three hard ceramics were selected since they have been used frequently by different investigators due to their high hardness and rigidity as composite reinforcements and coating layers [23][24][25][26][27][28]. Also, five different tapered angles were picked up in order to conceive the impact of the geometrical factor.…”

Diffusion Nitride Surface Layers on Aluminum Substrates Produced by Hybrid Method Using Gas Nitriding

“…It was assumed that despite the very limited solubility of nitrogen in aluminum (2 × 10 −4 at.% [20]), diffusion may occur, especially by grain boundaries, and this may lead to precipitation processes, which should be beneficial in terms of potential precipitation hardening in the diffusion zone. In fact, the AlN aluminum nitride fine precipitates, due to their high hardness, high elastic modulus, and low coefficient of thermal expansion, may act as effective reinforcement particles as, e.g., demonstrated in [39]. It was also assumed that the presence of alloying elements in alloyed substrates may have a beneficial effect on the solubility of nitrogen in aluminum.…”