6.2(a) Flashcards
What is meant by the hardness of a material?
Hardness is the ability of a material to resist penetration, wear and indentation.
Explain what is meant by the strength of a material?
Strength is a material’s ability to withstand force, or resist stress without breaking.
Explain the term ductility in reference to materials?
Ductility is a material’s ability to be drawn or stretched into thinner sections without breaking.
Ductile materials are favored for aircraft design as they are easily formed and have a resistance to failure.
What is meant by the elastic limit of material?
The elastic limit is the point at which permanent deformation occurs.
The stress at which a material will rupture in tension, compression or shear is?
Ultimate strength
One cubic centimetre of water weighs one gram, and is said to have a density of one. Aluminium has a density of 2.7, what will a cubic
centimetre of aluminium weigh?
2.7 grams
What classification of material is aluminium?
Non-ferrous?
What is the raw material from which aluminium is made?
Bauxite
What is the melting point of aluminium?
660 ^C
In wrought aluminium alloys what alloy is portrayed by the AA numbering system 2024?
HT?
2XXX = Copper
AA = Aluminium Association
Heat Treatable
In wrought aluminium alloys what alloy is portrayed by the AA numbering system 3003?
HT?
3XXX = Manganese
AA = Aluminium Association
Non Heat Treatable
In wrought aluminium alloys what alloy is portrayed by the AA numbering system 5056?
HT?
5XXX = Magnesium
AA = Aluminium Association
Non Heat Treatable
In wrought aluminium alloys what alloy is portrayed by the AA numbering system 7075?
HT?
7XXX = Zinc
AA = Aluminium Association
Heat Treatable
In wrought aluminium alloys what alloy is portrayed by the AA numbering system 1100?
Pure Aluminium (99% min purity)
AA = Aluminium Association
Non Heat Treatable
How can the strength of 2024 aluminium alloys be increased?
Can be heat treated.
For maximum strength the metal must be quenched immediately so it will have the smallest grain size possible. This will offer good protection against corrosion.
How can the strength of aluminium alloy 5056 be increased?
Non heat treatable aluminium alloys are hardened by alloying and strain hardening.
‘Cold worked’, ‘work hardened’ and ‘strain hardened’ refer to hardening processes such as rolling, drawing, bending or pressing.
5XXX = Magnesium