铁碳相图告诉我们钢铁性能由什么决定？
What does the iron-carbon phase diagram tell us about steel properties?
它给出不同温度和含碳量下铁素体、奥氏体、渗碳体等相的稳定区域；通过控冷可得到珠光体、马氏体等不同组织，从而决定硬度与韧性。这是钢铁热处理与合金设计的基础。
It maps the stable regions of phases like ferrite, austenite, and cementite across temperature and carbon content; controlled cooling yields pearlite, martensite, and other microstructures that set hardness and toughness. It underpins heat treatment and alloy design.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
Callister《材料科学与工程导论》(Materials Science and Engineering: An Introduction)；Askeland《材料科学基础》
Callister, 'Materials Science and Engineering: An Introduction'; Askeland, 'The Science and Engineering of Materials'
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8 · 核验依据 2 ISBN 9781292247137 · 核验依据 3 ISBN 9781641950565 (2019)
#铁碳相图 #奥氏体 #马氏体 #热处理
什么是自修复材料？
What is a self-healing material?
自修复材料内部含微胶囊或可逆化学键，出现微裂纹时自动释放修复剂或重新结合，恢复性能。它可延长混凝土、涂层和聚合物的寿命。目前多用于防护和航天领域。
Self-healing materials contain microcapsules or reversible bonds that release healing agents or re-bond when microcracks appear, restoring properties. They can extend the life of concrete, coatings, and polymers. Today they are mostly used in protection and aerospace.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#自修复 #智能材料 #寿命
形状记忆合金（如镍钛诺）为什么能『记忆』形状？
Why can shape-memory alloys like Nitinol 'remember' a shape?
低温马氏体相时合金很容易被变形，加热回到高温奥氏体相后晶格自动恢复母相形状，这就是形状记忆效应。当温度高于奥氏体转变终了点时，加载会诱发应力马氏体、卸载后立即回复，表现为超弹性（伪弹性）。Buehler 等人在 1960 年代初于美国海军军械实验室发现镍钛诺。
In the low-temperature martensitic phase the alloy deforms easily, and heating it back into the high-temperature austenitic phase makes the lattice recover the parent shape—the shape-memory effect. Above the austenite finish temperature, loading induces stress-induced martensite that reverts on unloading, giving superelasticity (pseudoelasticity). Buehler and colleagues discovered Nitinol at the US Naval Ordnance Laboratory in the early 1960s.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Otsuka 与 Wayman《形状记忆材料》(Shape Memory Materials)；Buehler 等《镍钛诺》(1963)
Otsuka & Wayman, 'Shape Memory Materials'; Buehler et al., 'Nitinol' (1963)
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL19589033W：Shape memory materials
#形状记忆合金 #镍钛诺 #马氏体 #奥氏体
什么是形状记忆合金？
What is a shape memory alloy?
形状记忆合金（如镍钛诺）在受热后能从变形状态恢复原先形状，因晶体相变可逆。它用于血管支架、眼镜架和温控阀门。还能表现出超弹性。
A shape memory alloy such as Nitinol returns to its original shape after heating from a deformed state, thanks to a reversible crystal phase change. It is used in vascular stents, eyeglass frames, and temperature valves. It can also show superelasticity.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#记忆合金 #智能材料 #相变
3D 打印（增材制造）相比切削加工的根本优势是什么？
What is the fundamental advantage of 3D printing (additive manufacturing) over machining?
增材制造按三维模型逐层堆积材料，几乎不受复杂内腔与拓扑优化的几何限制，且材料浪费少；Hull 在 1984 年发明立体光刻(SLA)。它适合小批量、个性化与一体化构件。
Additive manufacturing builds material layer by layer from a 3D model, free of most geometry limits imposed by internal cavities and topology optimization, and wastes little material. Hull invented stereolithography (SLA) in 1984. It suits low-volume, personalized, and integrated parts.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
Gibson, Rosen & Stucker,《Additive Manufacturing Technologies》,2021 (DOI: 10.1007/978-3-030-56127-7)；Hull《立体光刻专利》(1986)
Gibson, Rosen & Stucker, 'Additive Manufacturing Technologies', 2021, DOI: 10.1007/978-3-030-56127-7; Hull, 'Stereolithography patent' (1986)
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1007/978-3-030-56127-7
#增材制造 #3D打印 #立体光刻 #拓扑优化
什么是拓扑绝缘体？
What is a topological insulator?
拓扑绝缘体体内绝缘而表面能导电，且表面电流受拓扑保护不易被杂质散射。它在自旋电子和量子计算中有潜力。2016年诺贝尔物理学奖与拓扑相研究相关。
A topological insulator is insulating inside but conducts on its surface, where currents are topologically protected from scattering by impurities. It has potential in spintronics and quantum computing. The 2016 Nobel Prize in Physics related to topological phase research.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#拓扑绝缘体 #量子 #新材料
什么是金属泡沫？
What is metal foam?
金属泡沫是内部充满气孔的多孔金属，密度低、吸能好且可隔音隔热。它用于缓冲吸能、散热和轻量化结构。制备常用发泡或粉末冶金法。
Metal foam is a porous metal full of internal voids, with low density, good energy absorption, and sound and heat insulation. It is used for cushioning, heat dissipation, and lightweight structures. It is usually made by foaming or powder metallurgy.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#金属泡沫 #多孔 #轻量化
什么是“时效强化”（沉淀强化）？以铝合金为例说明。
What is precipitation (age) hardening, and explain it using an aluminum alloy as an example?
时效强化先把合金固溶处理成过饱和固溶体，再在室温或升温下时效，析出细小弥散的第二相颗粒以阻碍位错运动，从而提高强度。例如 Al-Cu 系（如2024）在约190℃时效析出 θ' 相，强度显著提升。
Precipitation hardening first forms a supersaturated solid solution by solution treatment, then aging at room or elevated temperature precipitates fine, dispersed second-phase particles that impede dislocation motion and raise strength. For example, Al-Cu alloys such as 2024 aged near 190 ℃ form θ' precipitates and gain large strength.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
ASM International《金属手册》；Callister《材料科学与工程导论》
ASM International, 'ASM Handbook'; Callister, 'Materials Science and Engineering: An Introduction'
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8 · 核验依据 2 ISBN 9781292247137 · 核验依据 3 ISBN 9781641950565 (2019)
#时效强化 #沉淀强化 #铝合金 #第二相 #位错
什么是气凝胶？
What is an aerogel?
气凝胶是密度极低、孔隙率超90%的固态材料，多为二氧化硅骨架，隔热性能极佳。它轻到能托于花瓣上，用于航天隔热和保暖服。缺点是脆、成本高。
An aerogel is an extremely low-density solid with over 90% porosity, usually a silica skeleton, giving superb thermal insulation. It is so light it can rest on a petal, and is used in aerospace insulation and warm clothing. Its drawbacks are brittleness and cost.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#气凝胶 #隔热 #纳米材料
什么是铝合金？
What is aluminum alloy?
铝合金在铝中加入铜、镁等元素提高强度，同时保留轻质和耐腐蚀。它广泛用于飞机、汽车和门窗。通过热处理或加工硬化可进一步增硬。
Aluminum alloy adds elements like copper and magnesium to aluminum to raise strength while keeping it light and corrosion-resistant. It is widely used in aircraft, cars, and window frames. Heat treatment or work hardening can harden it further.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#铝合金 #轻金属 #耐腐蚀
什么是钛合金？
What is titanium alloy?
钛合金以钛为主加入铝、钒等，强度高、密度小、耐海水腐蚀且生物相容。它用于飞机发动机、植入物和化工设备。缺点是提炼难、价格高。
Titanium alloy is mainly titanium with aluminum and vanadium, offering high strength, low density, seawater corrosion resistance, and biocompatibility. It is used in jet engines, implants, and chemical equipment. Its drawbacks are difficult extraction and high cost.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#钛合金 #轻金属 #耐蚀
碳纤维复合材料为什么比钢既轻又强？
Why are carbon-fiber composites both lighter and stronger than steel?
碳纤维沿纤维方向的抗拉强度极高、密度却只有钢的约四分之一，把它埋入环氧树脂基体就得到比强度突出的层合板。缺点是各向异性、成本较高且层间易分层。
Carbon fibers have very high tensile strength along the fiber yet about one-quarter the density of steel; embedded in an epoxy matrix they form laminates with outstanding specific strength. Downsides are anisotropy, higher cost, and susceptibility to delamination.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Mallick《纤维增强复合材料》(Fiber-Reinforced Composites)；Askeland《材料科学基础》
Mallick, 'Fiber-Reinforced Composites'; Askeland, 'The Science and Engineering of Materials'
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL3927645W：The science and enginee
#碳纤维 #复合材料 #比强度 #各向异性
什么是铁碳相图？它如何区分钢与铸铁？
What is the iron-carbon phase diagram, and how does it distinguish steel from cast iron?
铁碳相图表示铁碳合金在平衡条件下各相随温度与成分的变化。含碳量低于约2.14%（质量分数）为钢，高于此值为铸铁；钢区包含铁素体、奥氏体、珠光体和渗碳体等组织。
The iron-carbon phase diagram shows the equilibrium phases of Fe-C alloys versus temperature and composition. Alloys with less than about 2.14 wt% carbon are steel, and above that are cast iron; the steel region includes ferrite, austenite, pearlite, and cementite.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
ASM International《金属手册》第1卷；Callister《材料科学与工程导论》
ASM International, 'ASM Handbook' Vol. 1; Callister, 'Materials Science and Engineering: An Introduction'
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8 · 核验依据 2 ISBN 9781292247137 · 核验依据 3 ISBN 9781641950565 (2019)
#铁碳相图 #钢 #铸铁 #珠光体 #奥氏体
什么是3D打印材料？
What are 3D printing materials?
3D打印材料按工艺不同有塑料丝、光敏树脂、金属粉末等，逐层堆积成型。它们让复杂形状无需模具即可制造。金属打印常用激光熔融铺粉工艺。
Depending on the process, 3D printing materials include plastic filament, photopolymer resin, and metal powder, built up layer by layer. They let complex shapes be made without molds. Metal printing often uses laser melting of a powder bed.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#3D打印 #增材 #材料
什么是碳纤维增强复合材料（CFRP）？它有哪些优势与局限？
What is carbon-fiber-reinforced polymer (CFRP), and what are its advantages and limitations?
CFRP 以碳纤维为增强相、聚合物为基体，具有极高的比强度和比刚度、耐腐蚀、疲劳性能好。局限在于成本高、呈各向异性且较脆、抗冲击损伤容限低、回收困难。
CFRP uses carbon fibers in a polymer matrix, giving very high specific strength and stiffness, corrosion resistance, and good fatigue behavior. Limitations are high cost, anisotropy and brittleness, low impact damage tolerance, and difficulty of recycling.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
矿物金属与材料学会（TMS）；Daniel & Ishai《复合材料工程》
The Minerals, Metals & Materials Society (TMS); Daniel & Ishai, 'Engineering Mechanics of Composite Materials'
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL3913841W：Engineering mechanics o
#碳纤维 #复合材料 #比强度 #各向异性 #回收
什么是“位错滑移”？位错为何能让金属轻易发生塑性变形？
What is dislocation slip, and why do dislocations let metals deform plastically so easily?
金属的塑性变形主要通过位错沿滑移系的滑移实现。位错只需很小应力即可逐排运动（切应力约为剪切模量的万分之一），远低于整层原子同时错动所需，这就解释了金属的优良延性。
Plastic deformation in metals occurs mainly by the slip of dislocations along slip systems. A dislocation moves one row at a time under a stress far smaller (about μ/10^4) than would be needed to shift whole atomic planes together, which explains the good ductility of metals.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
Hull & Bacon《位错导论》；Callister《材料科学与工程导论》
Hull & Bacon, 'Introduction to Dislocations'; Callister, 'Materials Science and Engineering: An Introduction'
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8 · 核验依据 2 ISBN 9781292247137 · 核验依据 3 ISBN 9781641950565 (2019)
#位错 #滑移 #塑性变形 #延性
什么是玻璃钢？
What is fiberglass (FRP)?
玻璃钢是玻璃纤维与树脂复合的材料，俗称FRP，质轻、强度高、耐腐不锈。它用于船体、储罐和汽车部件。但刚度不如金属且不耐高温。
Fiberglass, or FRP, is glass fiber embedded in resin; it is light, strong, and corrosion-proof. It is used for hulls, tanks, and car parts. But its stiffness is lower than metal and it does not withstand high heat.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#玻璃钢 #复合材料 #FRP
什么是陶瓷？
What is ceramic?
陶瓷是用黏土等无机物经高温烧结成的硬脆材料，耐高温、耐磨、绝缘。传统用于砖瓦器皿，先进陶瓷用于切削工具和航天隔热。缺点是脆、抗冲击差。
Ceramic is a hard, brittle material made by firing clay and other inorganic substances at high temperature; it is heat-resistant, wear-resistant, and insulating. Traditional uses are bricks and tableware, while advanced ceramics serve cutting tools and aerospace heat shields. Its drawback is brittleness.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#陶瓷 #烧结 #无机
什么是混凝土？
What is concrete?
混凝土由水泥、砂、石和水拌合后硬化而成，抗压好但抗拉差。它便宜、可塑性强，是用量最大的建筑材料。常配钢筋形成钢筋混凝土使用。
Concrete is made by mixing cement, sand, gravel, and water that hardens; it is strong in compression but weak in tension. It is cheap and highly formable, the most used building material. It is often paired with steel as reinforced concrete.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#混凝土 #水泥 #建材
什么是钢？
What is steel?
钢是以铁为主、加入少量碳（通常低于2%）的合金，强度高且可焊可锻。它是建筑、汽车和机械最重要的结构材料。按成分可分为碳素钢和合金钢。
Steel is an alloy based on iron with a small amount of carbon, usually under 2%, giving high strength and good weldability and formability. It is the most important structural material for buildings, cars, and machines. It is divided into carbon steel and alloy steel by composition.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#钢材 #合金 #结构材料
什么是塑料？
What is plastic?
塑料是以高分子树脂为主、可塑制成型的合成材料，质轻、耐腐蚀、绝缘好。它来自石油或可再生原料，用途极广。但难降解，带来白色污染问题。
Plastic is a synthetic material based on polymer resin that can be molded; it is light, corrosion-resistant, and a good insulator. Derived from petroleum or renewable feedstocks, it is used almost everywhere. But it is hard to degrade, causing white pollution.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Callister,《Materials Science and Engineering: An Introduction》Wiley 多版
W. D. Callister Jr., Materials Science and Engineering: An Introduction, Wiley, various editions
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8
#塑料 #高分子 #材料
为什么玻璃是“非晶态”固体而不是晶体？
Why is glass an amorphous solid rather than a crystalline one?
玻璃在冷却时速度太快，原子来不及排成周期性晶格，被“冻结”成类似液体的无序结构，因此没有长程有序，也没有固定的熔点，而是在一个温度范围内逐渐软化。所以玻璃属于非晶态固体，与金属、陶瓷等晶体材料在原子排列上截然不同。
When glass cools it does so too fast for atoms to arrange into a periodic lattice, so they are frozen into a liquid-like random structure with no long-range order. It therefore has no sharp melting point but softens over a temperature range, so glass is an amorphous solid distinct from crystalline metals and ceramics.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-10-03 · 3 条独立证据
来源 · Source
美国材料与试验协会（ASTM）；Callister《材料科学与工程导论》
ASTM International; Callister, 'Materials Science and Engineering: An Introduction'
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-119-45520-2 (Global Ed.) / 978-1-119-45391-8 · 核验依据 2 ISBN 9781292247137 · 核验依据 3 ISBN 9781641950565 (2019)
#玻璃 #非晶态 #长程无序 #软化