Editing Metal matrix composite (section)

{{Short description|Composite material consisting of fibers or particles in a metallic matrix}}

In [[materials science]], a '''metal matrix composite''' ('''MMC''') is a [[composite material]] with fibers or particles dispersed in a metallic [[Matrix (composite)|matrix]], such as [[copper]], [[Aluminium|aluminum]], or [[steel]]. The secondary phase is typically a [[ceramic]] (such as [[Aluminium oxide|alumina]] or [[Silicon carbide fibers|silicon carbide]]) or another metal (such as steel<ref>{{Cite journal |last1=Gopi Krishna |first1=M. |last2=Praveen Kumar |first2=K. |last3=Naga Swapna |first3=M. |last4=Babu Rao |first4=J. |last5=Bhargava |first5=N.R.M.R. |date=2018|title=Metal-metal Composites-An Innovative Way For Multiple Strengthening |journal=Materials Today: Proceedings |volume=4 |issue=8 |pages=8085–8095 |doi=10.1016/j.matpr.2017.07.148 |issn=2214-7853}}</ref>). They are typically classified according to the type of [[Reinforcement (composite)|reinforcement]]: short discontinuous fibers (whiskers), continuous fibers, or particulates. There is some overlap between MMCs and [[cermet]]s, with the latter typically consisting of less than 20% metal by volume. When at least three materials are present, it is called a '''hybrid composite'''. MMCs can have much higher [[Specific strength|strength-to-weight ratios]],<ref>{{Cite book |last=Dieter |first=George E. |title=Mechanical metallurgy |date=1986 |publisher=McGraw-Hill |isbn=0-07-016893-8 |edition=3rd |location=New York |pages=220–226 |oclc=12418968}}</ref> [[stiffness]], and [[ductility]] than traditional materials, so they are often used in demanding applications. MMCs typically have lower [[Thermal conductivity|thermal]] and [[electrical conductivity]] and poor resistance to radiation{{Citation needed|date=March 2022}}, limiting their use in the very harshest environments.