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one-phase chemical compound

mechanical mixture of powders

Al and Si based alloy

Which methods are used for technical ceramics hardness measurement?

Vickers method with hardmetal ball

Rockwell method and diamond cone

Ball indentation hardness

Brinell's method and a steel ball

Vickers method and diamond pyramid

Hot isostatic pressing is not a viable option for production of technical ceramics if the chief criterion is

zero porosity

strength without grain growth

processing refractory ceramics

low cost

The main groups of technical ceramics are

non-oxide ceramics

mixed ceramics

oxide ceramics

carbide ceramics

Why are ceramic materials generally brittle?

Ceramic crystal structure comprises of ionic and covalent bonds

ceramic contains pores

Ceramic structures always contain defects (dislocations and vacancies)

ceramics contains glass phase

The following ceramic compound is widely used as pigment in paints

ZrO2

SiO2

UO2

TiO2

What are the properties of technical ceramics compared to steel?

Technical ceramics density is usually lower

Steel hardness is significantly lower

Steel toughness is lower

Steel tensile strength is higher

Technical ceramics are more easily machinable

Ceramic composites are manufactured using

hot-pressing

casting into high-temperature molds

reactive sintering

high-temperature self-propagating synthesis

Which of following statements are true for powder metallurgy?

Powders of ceramic compound or mixture of several compounds are mixed (milled), pressed and heated, but melting temperature is not exceeded. Only partial melting may occur (in case of mixture of several compounds).

During sintering the powder particles fuse together thereby lowering the melting point and increasing the uniformity of material.

Powders of ceramic compound or mixture of several compounds are mixed (milled), pressed and heated above melting temperature

During sintering the powder particles fuse together increasing materials density and properties