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