Crowdly

Can alloying elements increase strength and hardness?

No, they do not affect hardness and strength

In some cases increase, however the effect is very small

In most cases, they increase both hardness and strength

Affect depending on carbon content

Choose the correct phrase

Only if the amount of impurity atoms is higher than 40% the properties of the material can be changed

In the substitutional solid solutions the atoms or ions replace the host atoms or ions

In metal alloys the metal's atomic radii should be quite different in order to solve into each other

Impurity atoms cannot change the properties of the materials significantly

Which statements are correct about spheroidal graphite ductile cast iron?

Spheroidal graphite is obtained from the solid state by annealing

Spheroidal graphite is formed from the molten state by the addition of modifiers

The microstructure of the spheroidal graphite iron may contain ledeburite and cementite

It is stronger and more ductile compared to flake and nest graphite cast iron (considering the effect of graphite shape on mechanical properties)

Which alloys have the highest specific strength?

Heat-resistant steels

Alloyed steels

Titanium alloys

Magnesium alloys

Which statements are correct about the classification and strength properties of steel and cast iron?

The strength of the cast iron is in the range Rm = 100 ... 1000 MPa

The carbon content of cemented steels is 0.05 ... 0.25%

Cast iron is better than steel in terms of strength

Tools made from cast irons have better service life than tools made from steels

Which statements are correct about tool steels?

Tool steels are heat treated to the required hardness (between 45 ... 64 HRC)

Tool steels are used in building structures

Punches and injection molds are made of tool steels

Tool steels are not heat treated

What is the type and composition of the alloy AC-AlSi13?

castable aluminium alloy, 13%Al

Silicon bronze, 13%Si

Silumin (Aluminium-Silicon alloy), 13%Si

Aluminium bronze, 13%Si

Steels are classified according to their chemical composition:

low alloy steels

high alloy steels

low alloy steels (alloying elements below 10%)

high alloy steels (alloying elements concentration above 10%)

What is the designation of deformable aluminum alloys according to EN?