材料成型级控制工程专业英语阅读
1.2.1 Plain Carbon Steel 普通碳钢
Hot-rolled steel delivered （供给）by steelmaking works as rolled sections(bars, beams，sheets．tubes，etc) is the most wildly used material for manufacture of various machines，machine tools, building structures，consumer goods，etc．Delivered steel should have the properties as specified by State Standards（国家标准）．
钢铁制造车间供给的热轧钢主要为棒材、柱材、板材、管材等，热轧钢是制造各种机械、机器工具、建筑结构和消费品中应用最广泛的材料。所供给的钢应具有国家标准规定的各种性能。
In the RSSU．Plain carbon steels are classified into three groups：A, B and C，depending on their application.
在RSSU中，普通碳钢根据其用途分为A、B、C三类。
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（保证） mechanical properties，while the chemical composition is not guaranteed（保证、担保）．
A:如果钢在制造产品的过程中没有进行热加工（焊接、锻造等），则最终产品的组织和性能将与轧厂提供的相同。
这种情况下，用户只需要求材料应有的机械性能，而不必保证其成分。
B: If a steel is to be subjected to hot working(forging，stamping，etc)，its initial structure and mechanical properties will be changed.In that case the composition of the steel will be of prime importance for the user，since it determines the conditions of hot working and the final mechanical properties of steel products．Now a steel of warranted composition is delivered to the user.
B.如果钢要进行热加工（锻造、冲压等），则其初始组织和机械性能将会改变。此时/在这种情况下，钢的成分对用户来讲是最重要的，因为它(成分)决定了热加工的条件，钢制品的最终机械性能。因此，提供给用户的钢应保证其成分含量。
C: If a steel is to be welded．the user wants to know the composition of the steel．since it determines the properties of the metal in the zone subjected to thermal effect of weld（焊接热影响区）．The user is also interested in the initial mechanical properties of the metal，since these properties will remain the same in portions not subjected to welding．In that case the metal is delivered with warranted composition and mechanical properties.
C．如果钢要进行焊接，则用户需要知道钢的成分，因为成分决定钢焊接时热影响区的性能。用户也会对钢材的原始机械性能感兴趣，因为未焊接的部分的性能是原始性能。这种情况下，供给用户的钢应具有规定的成分和机械性能。
General-purpose 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/一般用途的普通钢不是合金钢。一些合金元素偶尔会出现，其含量受限制。
The presence of silicon and manganese may be due to the steel—making process(the necessity of deoxidation脱氧)．Surphur（硫）and phosphorus（磷） are harmful impurities（杂质） in steel and their content should be minimized as it may affect the quality of steel．
在钢冶炼过程中由于脱氧的需要，会出现硅和锰。硫、磷是钢中有害的杂质，应尽可能减少其含量，它们会影响钢的质量。
The principal element whose content is responsible for the properties of steels is carbon
影响钢性能最主要的元素是碳。
1.3Non-ferry Alloys
Although ferrous alloys ale used in the majority of metallic applications in current engineering designs，non—ferrous alloys play a large and indispensable role in our technology. As compared to ferrous alloys，the list of non—ferrous alloys is，of course，long and complex．We shall briefly list the major families of non—ferrous alloys and their key attributes．
尽管现代工业设计中，铁合金是主要应用的金属，但是非铁合金在当前科技中也起着很大并不可替代的作用。当然，与铁合金相比，非铁合金的种类多且复杂。我们将简要介绍几种非铁合金及其主要特征。