【正文】 證明他們是必不可少的。工程設(shè)計(jì)要求結(jié)構(gòu)承重或電力傳輸大多數(shù)涉及鐵合金。由于金屬鍵，金屬塑性變形能力和自我強(qiáng)化的塑性變形。尤其是在模具彎曲這個(gè)領(lǐng)域。對(duì)于超塑性流動(dòng)特性完整的特征，但是，應(yīng)變誘導(dǎo)硬化的特性是必要的。通常選擇作為超塑性成形性質(zhì)的度量參數(shù)是在最佳超塑性溫度和應(yīng)變速率時(shí)的拉伸伸長(zhǎng)率。coolingandof(hypereutectoidaftermetalissolidsolidoftaketheandthetemperatures. 淬火是加熱到臨界點(diǎn)以上,Ac3,隨后快速冷卻。increasingintobyisorandiscalledrecrystallizationWithof優(yōu)秀的防腐性能以及其他各種性能使這些金屬及其合金應(yīng)用非常昂貴。Lead alloys are durable and versatile materials. The lead pipes installed by the Romans at the public baths in Bath, England, nearly 2000 years ago are still in use. Lead’s high density and deformability bined with a low melting point adds to its versatility．Lead alloys find use in battery grids (alloyed with calcium or antimony), solders (alloyed with tin), radiation shielding，and sound control structures. The toxicity of lead restricts design applications and the handling of its alloys.鉛合金是耐用的多功能材料。Cu－Ni合金已是典型的完全固溶例子。優(yōu)良的熱導(dǎo)率使其應(yīng)用于散熱器和熱交換器上。其表面形成致密的氧化膜，使其就有優(yōu)良的抗腐蝕性。電導(dǎo)率、易加工以及好的外觀也是其具有吸引力的特征。一些合金元素偶爾會(huì)出現(xiàn)，其含量受限制。這種情況下，用戶只需要求材料應(yīng)有的機(jī)械性能，而不必保證其成分。A: If a steel is to be used for making products without hot working (welding, Forging．Etc.). Its structure and properties in the final product will be the same as delivered from the rolling mill．In that case the user requests for a steel of warranted（保證） mechanical properties，while the chemical position is not guaranteed（保證、擔(dān)保）．A:如果鋼在制造產(chǎn)品的過(guò)程中沒(méi)有進(jìn)行熱加工（焊接、鍛造等），則最終產(chǎn)品的組織和性能將與軋廠提供的相同。Generalpurpose plain steels are not alloyed．Some alloying elements may sometimes be present in them occasionally and their content（含量） is limited．非特殊用途/一般用途的普通鋼不是合金鋼。Aluminum alloys are best known for low density and corrosion resistance. Electrical conductivity，easy of fabrication，and appearance are also attractive features．Because of these，the world production of aluminum roughly doubled in one recent 10 year period．Ore reserves for aluminum are large (representing 8％of the earth’s crust) and aluminum can be easily recycled鋁合金以其低密度和腐蝕抗力而聞名。一旦形成鈦合金，鈦的活性顯現(xiàn)出其優(yōu)點(diǎn)。優(yōu)良的電導(dǎo)率使銅合金成為電線的首選材料。熱處理時(shí)添加2wt％的鈹元素，產(chǎn)生的CuBe沉淀相使其拉伸強(qiáng)度可超過(guò)1000MPaNickel alloys have much in mon with copper alloys．We have already used the CuNi system as the classic example of plete solid solubility. Monel is the name given to mercial alloys with NiCu ratios of roughly 2:1 by weight. These are good examples of solution hardening. Nickel is harder than copper, but Monel is harder than nickel. 鎳合金比銅合金更普通。鐵合金上鍍鋅層是重要的防腐蝕措施，該方法稱之為鍍鋅。The precious metals include gold, iridium, osmium, palladium, platinum, rhodium，ruthenium，and silver. Excellent corrosion resistance bined with various inherent properties justify the many costly applications of these metals and alloys．Gold circuit in the electronics industry, various dental alloys, and platinum coatings for catalytic converters are a few of the better, known examples.貴重金屬包括金、銥、鋨、鈀、鉑、銠、釕和銀。consistingcooling.fullissteelequilibriumpearlite,followeddeposesWithlowerlowered,finedispersesothatnotdepositionrhardeningthe(Accm),ferriteprocedureAc1certain需要的超塑性行為的總體特征的處理變量在本節(jié)進(jìn)行了介紹。在較高的應(yīng)變率，應(yīng)變硬化與位錯(cuò)胞形成有關(guān)以一種典型的方式。Pressworking operations have increased dramatically over the last few years, but like many other manufacturing operations, the existing technology has sometimes failed to keep pace with the changing applications. One area where this is especially true is die bending. 在過(guò)去的幾年里壓力加工行業(yè)日益昌盛，但像許多其他制造業(yè)務(wù)一樣，現(xiàn)有的技術(shù)有時(shí)無(wú)法跟上不斷變化的應(yīng)用的步伐。這些類型的債券是剛性的，是由于兩個(gè)不同的電荷離子的靜電引力。這代表了范圍廣泛的組織工程材料的一個(gè)巨大的家庭及相關(guān)性質(zhì)。這些合金元素都經(jīng)過(guò)精心挑選，因?yàn)樗麄兛偸菐?lái)大幅增加材料成本。這些過(guò)程，這是熱激活，導(dǎo)致一個(gè)流動(dòng)應(yīng)力，應(yīng)變率和溫度，以及依賴于應(yīng)變。已變形引入的缺陷的強(qiáng)化作用表示贊賞多年，它已被用于提高，特別是在金屬和合金的冷加工技術(shù)實(shí)力水平的一種手段。在早期的鍛造天是塑造金屬加熱和錘擊的過(guò)程。從技術(shù)上講，鍛造可給金屬的過(guò)程中定義的塑造，提煉，并改善其機(jī)械性能的影響或壓力下，通過(guò)控制塑性變形的效用增加。 雖然不是在國(guó)民生產(chǎn)總值的巨大的商業(yè)鍛造業(yè)，它是一個(gè)巨人的貢獻(xiàn)我們的生活和我們的國(guó)防的標(biāo)準(zhǔn)。