Engineering Materials Flashcards: Plastics, Metals and Processing
96 English cards on material properties, metal and polymer families, manufacturing processes, and qualified selection cases, including sourced ABS and PA6 grades.
اس ڈیک کے بارے میں
Learn engineering materials through concise retrieval and constrained selection problems. These 96 original English cards connect property vocabulary, metal and polymer families, processing mechanisms and practical evidence checks.
Practise concept-to-explanation recall, selected situation-to-property or process choices, alloy-family recognition, and named-grade interpretation for ABS (INEOS Terluran GP-22) and PA6 (BASF Ultramid B3S and B3EG6). A suggested material or process is a screening candidate, not a qualified design.
The sequence introduces properties, then metals, polymers and manufacturing processes. Each topic progresses from mechanisms to applications. Selected case variants are separated from their foundation cards; the review scheduler handles later spacing.
Excluded: automatic reverse cards for every definition, generic numerical property rankings, machine settings, full phase diagrams and design allowables. Exact material properties require the correct grade, test method, temperature, moisture state, orientation and processing history. This is an evergreen topic deck, not a complete materials course or exam syllabus.
AI-assisted questions, answers and generated cover were independently composed and checked against technical sources. No private learner cards, textbook exercises, exam questions or third-party images were copied. Original wording, organization and generated media are offered under CC0 1.0 to the extent applicable rights exist; facts and third-party source material retain their own status.
Factual references include INEOS Terluran GP-22, BASF Ultramid, University of Illinois materials principles, Instron materials testing terms, TWI injection moulding and American Foundry Society metalcasting.
Independent educational material; no affiliation with or endorsement by the named manufacturers, technical bodies or universities.
اس ڈیک کے کارڈز
کارڈ 1
سوال
Engineering stress in a tensile test: force divided by what?
جواب
Original specimen cross-sectional area.
کارڈ 2
سوال
Engineering strain in a tensile test: extension divided by what?
جواب
Original gauge length. Strain is dimensionless.
کارڈ 3
سوال
Elastic deformation: what happens after unloading?
جواب
The deformation recovers.
کارڈ 4
سوال
Young’s modulus describes which material behaviour?
جواب
Resistance to elastic tensile or compressive strain, in the linear elastic region.
کارڈ 5
سوال
Yield strength marks the onset of what?
جواب
Significant permanent deformation, using the specified yield or proof criterion.
کارڈ 6
سوال
Ultimate tensile strength: which point on an engineering stress–strain curve?
جواب
The maximum engineering tensile stress.
کارڈ 7
سوال
Ductility describes what happens before tensile fracture?
جواب
How much plastic deformation the material can undergo.
کارڈ 8
سوال
Indentation hardness measures resistance to what?
جواب
Localized permanent penetration by an indenter.
کارڈ 9
سوال
Tensile toughness: what does the area under the stress–strain curve to fracture represent?
جواب
Energy absorbed per unit volume up to fracture under those test conditions.
کارڈ 10
سوال
Density relates which two quantities?
جواب
Mass per unit volume.
کارڈ 11
سوال
Thermal conductivity describes which ability?
جواب
Transferring heat through a material under a temperature gradient.
کارڈ 12
سوال
Electrical conductivity describes which ability?
جواب
Carrying electric current under an electric field.
کارڈ 13
سوال
Creep: what changes under a sustained load over time?
جواب
Deformation increases with time; temperature and stress affect the rate.
کارڈ 14
سوال
Fatigue damage is associated with what loading pattern?
جواب
Repeated or fluctuating loading that can initiate and grow cracks.
کارڈ 15
سوال
Brittle fracture: how much plastic deformation precedes it?
جواب
Little plastic deformation compared with ductile fracture under the same test conditions.
کارڈ 16
سوال
A bracket bends too far but recovers fully. Which property should you examine first?
جواب
Elastic stiffness: material modulus together with the bracket’s geometry.
کارڈ 17
سوال
A metal clip stays bent after one overload. Which threshold was exceeded locally?
جواب
Its yield threshold; permanent deformation occurred.
کارڈ 18
سوال
A housing must absorb a drop without fracture. Which evidence matters beyond tensile strength?
جواب
Impact-test performance under relevant temperature, notch and geometry conditions.
کارڈ 19
سوال
Two materials have equal yield strength. Must their tensile toughness be equal?
جواب
No. Different ductility can produce different energy absorption before fracture.
کارڈ 20
سوال
A plastic clamp slowly loosens at fixed deflection. Which time-dependent effect is this?
جواب
Stress relaxation: the stress decreases while the imposed deformation is held.
کارڈ 21
سوال
Does a higher hardness alone prove a part will resist every wear mechanism?
جواب
No. Wear also depends on contact, loading, lubrication and the wear mechanism.
کارڈ 22
سوال
Why compare impact results only with matching test conditions?
جواب
Specimen geometry, notches, temperature and test method affect measured impact behaviour.
کارڈ 23
سوال
Can a generic family property range serve as a finished-part design allowable?
جواب
No. Select a grade, condition and relevant design data before qualifying the part.
کارڈ 24
سوال
A lighter material is proposed for the same-size part. Which property predicts its mass change?
جواب
Density, provided the volume remains the same.
کارڈ 25
سوال
Ferrous versus nonferrous metals: what is the defining distinction?
جواب
Whether iron is the main constituent. Nonferrous does not mean completely iron-free.
کارڈ 26
سوال
Steel belongs to which basic alloy family?
جواب
Iron-based alloys containing carbon, often with other alloying elements.
کارڈ 27
سوال
Why specify a steel grade and heat treatment rather than just “steel”?
جواب
Composition and processing change its microstructure and mechanical properties.
کارڈ 28
سوال
What is a grain in a polycrystalline metal?
جواب
A crystalline region with a particular lattice orientation.
کارڈ 29
سوال
What separates neighbouring metal grains with different orientations?
جواب
A grain boundary.
کارڈ 30
سوال
Which crystal defect commonly moves during plastic deformation of metals?
جواب
A dislocation.
کارڈ 31
سوال
Cold working usually trades increased strength for what?
جواب
Reduced ductility, as plastic deformation impedes further dislocation motion.
کارڈ 32
سوال
What is a common purpose of annealing a cold-worked metal?
جواب
Restore ductility and reduce hardness through a controlled heat treatment.
کارڈ 33
سوال
Quenching in metal heat treatment means what cooling step?
جواب
Rapid cooling using a specified medium; the appropriate regime depends on the alloy and intended result.
کارڈ 34
سوال
What gives stainless steel much of its corrosion resistance?
جواب
A thin chromium-rich passive surface film.
کارڈ 35
سوال
Why distinguish grey cast iron from ductile cast iron during selection?
جواب
Graphite form and resulting mechanical behaviour differ; “cast iron” is not one property set.
کارڈ 36
سوال
Why are aluminium alloys often screened for lightweight structures?
جواب
Their relatively low density can help reduce mass; stiffness, strength and geometry still need checking.
کارڈ 37
سوال
Why is copper often screened for electrical conductors?
جواب
High electrical conductivity; cost, strength and connection design also matter.
کارڈ 38
سوال
Brass is principally an alloy of copper with which element?
جواب
Zinc.
کارڈ 39
سوال
Traditional tin bronze is principally an alloy of which two elements?
جواب
Copper and tin. Other bronze families use different alloying additions.
کارڈ 40
سوال
Does “stainless” mean immune to chloride corrosion?
جواب
No. Grade, environment and surface condition still govern corrosion resistance.
کارڈ 41
سوال
Two dissimilar metals touch in salty water. Which corrosion mechanism should be checked?
جواب
Galvanic corrosion, because electrical contact and an electrolyte can form a galvanic couple.
کارڈ 42
سوال
Can you rank aluminium and steel parts by stiffness using only their material names?
جواب
No. Compare the actual moduli and part geometries for the required loading.
کارڈ 43
سوال
A copper alloy is stronger than pure copper. Must it conduct electricity equally well?
جواب
No. Alloying changes conductivity as well as mechanical properties; check that alloy’s data.
کارڈ 44
سوال
A steel sheet cracks during forming after extensive cold work. What processing step may restore formability?
جواب
An appropriate anneal before further forming; confirm the alloy-specific procedure.
کارڈ 45
سوال
What is a common purpose of tempering a quench-hardened steel?
جواب
Improve toughness and ductility, usually with some reduction in hardness.
کارڈ 46
سوال
How can an insulating washer help a dissimilar-metal joint resist galvanic corrosion?
جواب
By interrupting the electrical connection, if the whole joint is electrically isolated.
کارڈ 47
سوال
Before approving a welded metal component, which material region besides the weld metal needs consideration?
جواب
The heat-affected zone, whose thermal cycle can change properties without melting it.
کارڈ 48
سوال
What is the key processing–structure–property lesson for metal selection?
جواب
A chemical composition alone does not determine performance; processing changes microstructure.
کارڈ 49
سوال
A polymer is built from what kind of molecular structure?
جواب
Large molecules containing many linked repeating units.
کارڈ 50
سوال
Which polymer class can usually be reheated and reshaped: thermoplastics or cured thermosets?
جواب
Thermoplastics. Cross-links in a cured thermoset prevent ordinary melt reshaping.
کارڈ 51
سوال
What deformation behaviour distinguishes an elastomer?
جواب
It can undergo substantial deformation and recover toward its original shape when the load is removed, within its working range.
کارڈ 52
سوال
What does “semi-crystalline polymer” mean?
جواب
Ordered crystalline regions coexist with amorphous regions.
کارڈ 53
سوال
Which polymer regions undergo glass transition: amorphous or crystalline?
جواب
Amorphous regions. Around the glass transition, motion of chain segments becomes much easier.
کارڈ 54
سوال
What structural feature prevents a cured thermoset from flowing like a thermoplastic melt?
جواب
A covalently cross-linked network.
کارڈ 55
سوال
Why are plasticizers added to some polymer formulations?
جواب
To increase flexibility; the amount and compatibility affect the final properties.
کارڈ 56
سوال
Why add UV stabilizers to a polymer intended for outdoor exposure?
جواب
To reduce degradation caused by ultraviolet exposure; the formulation and exposure still need verification.
کارڈ 57
سوال
Why can adding glass fibres make moulded polymer properties direction-dependent?
جواب
Fibres become oriented during flow, so reinforcement differs with direction.
کارڈ 58
سوال
What structural change separates glass transition from crystalline melting in a polymer?
جواب
Glass transition increases chain-segment mobility in amorphous regions; melting breaks down the ordered crystalline regions.
کارڈ 59
سوال
ABS is an abbreviation for which polymer name?
جواب
Acrylonitrile butadiene styrene.
کارڈ 60
سوال
PA6 is another name for which polyamide?
جواب
Polyamide 6, also called nylon 6.
کارڈ 61
سوال
Why distinguish “dry” from “conditioned” polyamide property data?
جواب
Moisture conditioning changes the material state and can change mechanical behaviour.
کارڈ 62
سوال
Does one grade’s ABS datasheet establish the properties of every ABS grade?
جواب
No. Formulation, grade, test method and conditions must match the claim.
کارڈ 63
سوال
INEOS Terluran GP-22 is specified for which main shaping process?
جواب
Injection moulding; it is a general-purpose ABS grade.
کارڈ 64
سوال
BASF Ultramid B3S is supplied for which main shaping process?
جواب
Injection moulding; BASF describes this PA6 grade as easy-flowing and finely crystalline.
کارڈ 65
سوال
A warm polymer bracket carries a constant load for months. Which data are needed beyond a short tensile test?
جواب
Long-term creep data for the relevant load, temperature and material condition.
کارڈ 66
سوال
Ultramid B3EG6 differs from unreinforced PA6 by which reinforcement?
جواب
BASF specifies glass-fibre reinforcement for this PA6 injection-moulding grade.
کارڈ 67
سوال
Which part category does INEOS identify as a particular application for Terluran GP-22?
جواب
Housings, including appliance housings. This is a candidate application, not automatic design approval.
کارڈ 68
سوال
Why keep opened Ultramid B3S granule containers carefully closed?
جواب
To limit moisture absorption before processing.
کارڈ 69
سوال
Can glass-filled PA6 data replace unfilled PA6 data in a design check?
جواب
No. Reinforcement changes the material; use the exact grade and relevant orientation data.
کارڈ 70
سوال
Must a thermoplastic part be accepted by the local recycling system?
جواب
No. Remeltability alone does not establish collection, sorting or recycling compatibility.
کارڈ 71
سوال
For an outdoor ABS housing, is a good indoor impact result enough evidence?
جواب
No. Check weathering, temperature and the exact grade’s suitability for the exposure.
کارڈ 72
سوال
BASF lists grips and fixing clamps for Ultramid B3S. What remains to verify for a loaded clamp?
جواب
Grade-specific long-term behaviour at the actual temperature and moisture state, plus the part geometry.
کارڈ 73
سوال
Metal casting shapes a part by which change of state?
جواب
Liquid metal solidifies inside a mould.
کارڈ 74
سوال
Forging shapes metal by what basic mechanism?
جواب
Compressive plastic deformation of solid metal; it may be performed hot or cold.
کارڈ 75
سوال
Extrusion is particularly suited to which basic geometry?
جواب
A continuous length with a substantially constant cross-section, formed through a die.
کارڈ 76
سوال
CNC machining is additive or subtractive?
جواب
Subtractive: controlled cutting removes material from a workpiece.
کارڈ 77
سوال
Injection moulding of a thermoplastic: what happens after the cavity fills?
جواب
The melt cools and solidifies before the part is ejected.
کارڈ 78
سوال
Thermoforming starts from which form of plastic stock?
جواب
A sheet heated until formable, then shaped over or into a mould.
کارڈ 79
سوال
Blow moulding is commonly used for which type of plastic part?
جواب
Hollow parts, such as bottles, formed by inflating a heated preform or tube in a mould.
کارڈ 80
سوال
Additive manufacturing builds geometry by what basic approach?
جواب
Adding material, commonly layer by layer, from a digital model.
کارڈ 81
سوال
In milling, what typically rotates to remove material?
جواب
The cutting tool.
کارڈ 82
سوال
Why may a cast part still need machining?
جواب
Selected surfaces may need tighter tolerances or a better finish than the casting provides.
کارڈ 83
سوال
Sand casting and permanent-mould casting mainly differ in what tooling feature?
جواب
Sand moulds are expendable; permanent moulds are reused.
کارڈ 84
سوال
Why can injection moulding be costly for a very small production run?
جواب
Tooling cost is spread across too few parts; compare total cost at the required volume.
کارڈ 85
سوال
A long plastic tube has the same cross-section throughout. Which process is a natural first candidate?
جواب
Extrusion, followed by cooling and cutting to length.
کارڈ 86
سوال
A thin plastic packaging tray must be formed from sheet. Which process is a natural first candidate?
جواب
Thermoforming; check wall thinning and the required detail.
کارڈ 87
سوال
Why should a forged part’s grain flow be considered in design?
جواب
Deformation creates directional structure; the load direction and process route affect performance.
کارڈ 88
سوال
A design needs a few changing metal prototypes. Why consider CNC machining before buying a production mould?
جواب
It can make revised parts directly from stock without dedicated mould tooling.
کارڈ 89
سوال
What distinguishes a fusion-weld heat-affected zone from the fusion zone?
جواب
The heat-affected zone changes thermally but does not melt; the fusion zone melts and resolidifies.
کارڈ 90
سوال
Why clean and prepare a metal surface before applying a protective coating?
جواب
Contaminants and surface defects can impair coating adhesion and performance.
کارڈ 91
سوال
Does a corrosion-resistant coating make the underlying material irrelevant?
جواب
No. Damage, adhesion, exposure and substrate compatibility still matter.
کارڈ 92
سوال
Why check build orientation when selecting a layer-built polymer part?
جواب
Layer bonding and deposition can make strength depend on direction.
کارڈ 93
سوال
A hollow plastic bottle needs a shaped enclosed body. Which process family should you screen first?
جواب
Blow moulding; select the exact variant for the material and geometry.
کارڈ 94
سوال
Many identical thermoplastic housings are needed. Which process deserves early cost comparison?
جواب
Injection moulding, because repeat production can spread tooling cost over many parts.
کارڈ 95
سوال
Why does choosing a process also affect material selection?
جواب
Materials must tolerate that process and achieve the required finished-part properties.
کارڈ 96
سوال
Before releasing a selected material–process combination, what evidence closes the selection loop?
جواب
Verify the exact grade, processing condition and part performance against the actual requirements.
96 کارڈز
Engineering Materials Flashcards: Plastics, Metals and Processing
مطالعہ شروع کرنے کے لیے Nibomo کھلے گا۔