3272-6-Mat&Had (6.2)

For a particular metal material, what conditions are best to minimise creep?. Low stress, low temperature. Low stress, high temperature. High stress, low temperature.

What is the effect of precipitation heat treatment on aluminium?. It speeds up age hardening process. It delays the age hardening process. It softens the material to allow it to be worked.

Aluminium exposed to air will. oxidise and become weaker. oxidise and become electrically insulated. oxidise and become stronger.

What care should you take with 2024-T3?. Do not scratch or make nicks in it. Do not bend at sharp angles. Do not remove the surface of the sheet metal.

Composition of silver solder is. tin and lead. tin, lead and silver. tin, lead, silver and antimony.

If aluminium alloy is not quenched within the minimum time allowed after heat treatment is it will be. subject to corrosion. malleable. brittle.

Anodizing protects alloy metal from corrosion and does what else?. Seals the surface from moisture. Makes a good surface for paint to adhere to. Makes the surface alkaline.

If caustic soda turns a material black what is it?. Aluminium alloy. Alclad. Aluminium.

What chemical is used to identify aluminium alloys?. Caustic soda. Copper sulphate. Nitric acid.

Pure aluminium is. highly resistant to corrosion.. not resistant to corrosion. reasonably resistant to corrosion.

Precipitation treating makes the metal. Precipitation treating makes the metal. less strong and hard. harder, stronger and less ductile.

A material has the code 2024-TH6 on it. Which part of the code indicates the percentage of the alloying element?. H. 20. 6.

Aluminium alloyed primarily with magnesium is numbered. 2025. 5025. 1025.

Heat treatment is shown on a British aluminium alloy by a. letter and number code. number code. letter code.

Non heat treatable materials. cannot be hardened. can be hardened by strain hardening or cold working. can be hardened by annealing.

Which of the following metals is an aluminium silicon alloy used mainly for casting?. Alclad. Aldrey. Alpax.

Aircraft skin is joggled to. provide smooth airflow at faying surfaces. make a frame lighter but stronger. conform to the aircraft contour.

The British system of heat treatment codes is. a series of letters. numbers and letters. a series of numbers.

In a sheet metal store the following is marked on a sheet of aluminium alloy: L162 (sheet 1). , On a different sheet the following marking is found: L172 (sheet 2). The following is true: Sheet one has a shinier surface than sheet 2. Sheet one is more ductile than sheet 2. Sheet two is of a thicker gauge than sheet 1.

Cold working of a material is used to reduce. material hardness. fatigue. wear of manufacturing tools.

Sheet metal should be stored. above 25 degrees centigrade. on its edge in racks to prevent scratching. stacked flat to prevent bending of sheets.

Clad aluminium alloy (alclad) has a pure aluminium coating of. 0.002. 1% of alloy thickness. 5% of alloy thickness.

The main metal in monel is. aluminium. nickel. stainless steel.

A tube complying to BS T51 is. tungum. HTS tube. high pressure seamless copper tube.

Why is nickel chromium used in many exhaust systems?. Corrosion resistant and high heat conductivity. Lightweight and flexible. Corrosion resistant and low expansion coefficient.

Titanium alloys. are cheap to manufacture. have a high strength to weight ratio. are corrosion resistant but heavy.

Which part of the 2017-T36 aluminium alloy designation indicates the primary alloying agent used in its manufacture?. 20. 2. 17.

Clad aluminium alloys are used in aircraft because they. are harder wearing than unclad aluminium alloys. are less subject to corrosion than uncoated aluminium alloys. are stronger than unclad aluminium alloys.

Non heat treatable aluminium alloys. can be hardened by strain hardening. cannot be softened. cannot be hardened.

Solution treatment after manufacturers have performed it once can be carried out a further. 1 times. 2 times. 3 times.

Following solution treatment aluminium alloy can be placed into service. after 5 days. straigth away. after 24 hours.

The time between removal from heat treatment furnace and quenching must be not more than. 3 seconds. 10 seconds. 7 seconds.

When buffing surface of Aluminium Alloy, what material are you removing?. Oxide layer. Aluminium. Alloy.

Why is clad alloy preferred to pure Aluminium?. Less brittle. More ductile. Toughter.

Why are aluminium alloys used on aircraft, instead of pure aluminium?. Stronger. Corrosion resistant. Lighter.

The magnesium alloys used in aircraft can be recognized by. shiny surface due to chromium plated on the surface. yellowish surface due to protective treatment. silver surface due to protective coating.

Age hardening of aluminium is. never carried out. a gradual hardening over a period of time. not necessary.

Alclad is. aluminium with duralumin cladding. duralumin with aluminium coating. duralumin with magnesium cladding.

The oxide film on the surface of aluminium is. hard and porous. porous. non porous.

The process of forming a pure layer of aluminium over an aluminium alloy is. metalizing. cladding. electroplating.

Titanium can be identified by placing it on a grinding wheel and looking for. Red Sparks. Yellow Sparks. White Sparks.

The critical process of heat treatment is. temperature, method of heating and cooling. temperature and method of heating only. method of heating only.

Re-treatment of aluminium alloys can be performed by. alocrom treatment. brushing on phosphate treatment followed by paint. selenious acid treatment.

What is generally true for titanium alloy?. It is stronger than the aluminium. It is stronger than the steel. It has lower density than magnesium.

Malleable materials are. easy to forge. easy to cost. highly ductile.

If a material has to undergo deep cold forming operation. The essential property would be. ductility. malleability. elasticity.

The metal which must not be heated in a salt bath is. magnesium alloy. duralumin. rivets made of alclad.

The colour code on sheet metal indicates. only the specification of the material. the spec and gauge of the material. that the material is from an approved source.

When two or more metallic materials are fused together, the combination is known as. a composite material. a thermosetting compound. an alloy.

Malleable materials are normally. also highly ductile. easy to cast. easily forged.

The common bonding material for Tungsten Carbide is. Invar. Cobalt. Silicon.

Grain size will effect the mechanical properties of metal. Which of the following is true?. Large grain size is attributed to slow cooling rates and will give less tensile strength. Materials with large grain size are more prone to creep. Small grain size is normally attributed to rapid cooling rates and will give less tensile strength.

The cracking of structural members under repeated stress lower than the ultimate tensile load is known as. creep. fatigue failure. stress reversal.

The cracking of structural members under repeated stress lower than the ultimate tensile load is known as. creep. fatigue failure. stress reversal.

A sheet of metal is designated 2024-T4. The code tells us that the material is a copper based aluminium alloy. annealed and Naturally aged. solution treated and naturally aged. solution treated and artificially aged.

A metal is coded 1285 using the IADS coding method. This means the metal is. 85% pure aluminium. 99.85% pure aluminium. a copper based aluminium alloy i.e. duralumin.

A material containing approximately 66% nickel and 33% copper is known as. Nimonic. Monel metal. Invar.

Monel metal consists of approximately. 66% Copper and 33% Nickel. 66% Chromium and 33% Copper. 66% Nickel and 33% Copper.

Silver solder is composed of the materials. Copper, Tin and Silver. Zinc, Lead and Silver. Copper, Zinc and Silver.

What is fatigue?. Cyclic stressing of a part. Failure of a component due to corrosion. Constant stressing of a part.