Question

Evaluate the disadvantages of ceramic over metal when loaded under dynamic
loading.

Answer 1

Answer:

Ceramics now a days are used to make best of the products. Ceramics are the compounds of metals and non metals. Ceramics contains ionic bonding between them. Ceramics are made with silicon carbide, metal oxides,tungsten carbide, zirconia etc. Even though there are various advantage with the use of ceramics over metal in daily life. But some disadvantage are given below when ceramics are used for dynamic loading

Disadvantages of ceramics over metals when loaded for dynamic loading

• As ceramics are very difficult to shape and machine so proper dimensional properties which are required for ceramics can not be achieved
• Ceramics are having almost zero ductility and they are brittle in nature so when the ceramics are exposed to the dynamic loading there is inelastic deformation, fracture and fragmentation of ceramics takes place
• It is very difficult with Ceramics to achieve the good and high surface finish which make some vois and cavities in the ceramics to be formed and leads to failure of material when subjected to the dynamic laod condition while metals can be finished up to Ra .01 and lesser than that too
• Cremains material during operation and application are exposed to severe loading and high energy and velocity applications. Multi axes dynamic state of stress is also application some time during the use which cause rate dependent behaviour of the ceramics. Due to these loading the failure of ceramics takes place if there is irregularity is available in the material.
• Ceramics material when subjected to dynamic loading condition exhibits the strain rate hardening phenomenon and also there is single crack to multiple crack transition occurs which is known as fragmentation. It cause the failure of ceramics. If a crack is available in the ceramice material it can cause the failure of material when subjected to the dynamic load