**2. Manufacturing methodologies to fabricate the metal matrix composites**

The metal matrix composites (MMCs) composed of low-density magnesium reinforced with fibers or particles. MMCs offer high strength and high stiffness operating at higher temperatures and possess excellent wear-resistant properties as the properties are tailored according to required properties. However, MMCs have many disadvantages than metallic alloys, such as higher manufacturing costs for better performance and low ductility. This materials group has become attractive for the use in construction and functional applications. The demand for MMCs materials has been increased and is expressed in **Figure 1**.

The manufacturing methodologies are categorized into following

• Solid-state processing

*Magnesium Metal Matrix Composites and Their Applications DOI: http://dx.doi.org/10.5772/intechopen.96241*


Each process is further categorized and express in the following chart.

## **2.1 Solid-state processing**

The principal manufacturing methodologies included in solid-state processing are physical vapor deposition, powder blending and consolidation, and additive manufacturing.

### *2.1.1 Physical vapor deposition*

The fibers are continuously passed over the substrate of the metal with high partial pressure. The vapors produced are inserted in the process and condensed to make the coating on the surface. The deposition rate is 5-10 μm per minute. The coating fibers are consolidated by hot isostatic pressing. Sputtering is a physical vapor deposition method in which argon ions are used for bombarding catholically connected target to deposit the coating.

## *2.1.2 Powder blending and consolidation*

The magnesium powder is mixed with reinforcement to get uniformity under a neutral environment. The blending steps, along with powder size, control the mechanical properties of composites. The uniform and homogeneous mixture is compacted under controlled temperature. The oxides are supposed to be produced on the surface as magnesium is highly reactive to oxygen.

### *2.1.3 Additive manufacturing*

The reinforcements are uniformly distributed and dispersed in the matrix using 3D manufacturing techniques. The complex geometry and graded density

#### **Figure 1.**

*Manufacturing methodologies for MMCs.*

composites can be developed. The protection of magnesium powder from oxides is very critical in this method.
