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forgeability. Higher-carbon
steel is difficult to forge. Large grain size is best if subsequent heat treatment will refine the grain size.
Low-carbon,
nickel-chromium(铬) steels are
在高温下低碳，镍铬合金钢在受到520-ft·lb的冲击下表现出与相同碳含量普通钢几乎同样的塑性。镍减少了中碳钢的可锻性，但对低碳钢影响不大。铬在锻造温度下时使钢硬化，但钒没有明显的效果；两种加工方法对高碳钢没有影响。
just about as plastic at high
temperature under a single 520-ft·lb(1 ft·lb=1.35582J) blow as plain steels of similar
carbon content. Nickel decreases forgeability of medium-carbon steels, but has little effect on low-carbon
steels.
Chromium
seems to harden steel at forging temperatures, but vanadium(钒) has no discernible(可辨别的) effect; neither has the method of manufacture
any
effect
on
high-carbon steel.
Formability
成形
钢的冷成形是它的拉伸强度和延展性相结合的结果。拉伸强度和屈服点不能太高否则在
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The cold-formability of steel is a function(功能) of its tensile strength combined with ductility. The tensile strength and yield point must not be high 发生弯曲时需要做很多工作；与之相类似，钢
应该有高延展性，使其在没有断裂的情况下成形。加工力的大小取决于屈服点，因为钢在屈服点之上才开始变形。与此同时，加工硬化也同时发生，金属变得越来越硬，增加加工难度，尤其在低碳钢中容易发生。
or too much work will be required in bending（弯曲）; likewise（同样地）, the steel must have sufficient（充足的） ductility to flow to the required shape without cracking. The force required depends on the yield point,
because
deformation
starts in the plastic range above the yield point of steel. Work-hardening also occurs here, progressively（日益增多地）stiffening（使变硬） the metal and causing difficulty, particularly（独特的，显着的） in the low-carbon steels.
It is quite interesting in 谢谢欣赏
在这方面，相当有趣的是你将发现有时可
通过一次快速加载完成大拉伸，
但以缓慢的方
式两三次加载却不能实现。如果拉伸进行了一
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this connection（关于这一点，就此而论） to discover that deep draws can sometimes be made in one rapid operation that could not 半就停止了，那么在再加工之前应先退火，也
就是说工件是否有时间进行加工硬化。这不是一种科学的叙述方法，但确实是发生了。
possibly be done leisurely（缓慢地，从容不迫地） in two or three. If a draw is half made and then stopped, it may be necessary to anneal（退火） before proceeding, that is（换句话说）, if the piece is given time to work-harden. This may not be a scientific statement, but it is actually what seems to happen.
Internal stresses
Cold forming is done above the yield point in the work-hardening range, so internal stresses can be built up easily. Evidence of this is the springback（回弹） as the work leaves the forming operation and the warpage（翘曲，
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内应力
在高于屈服点的加工硬化区进行冷加工很容易产生内应力。例如工件停止成型加工后会发生回弹，在随后的热处理后，工件会发生翘曲。即使是一个简单的垫圈，由于打孔和随后的平整加工中产生内应力，也会在热处理中呈现严重的翘曲。
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扭曲） in any（任何一种） subsequent heat treatment. Even a simple washer might, by virtue of(依靠) the internal stresses resulting from punching（冲压） and then flattening（整平）, warp（弯曲） severely（严格地，激烈地） during heat treating. （virtue n.德行, 美德, 贞操, 优点, 功效, 效力, 英勇 believed in the virtue of prayer.相信祈祷的力量
When doubt exists as to（关于） whether internal stresses will cause warpage, a piece can be checked by heating it to about 1100 and then letting it cool. If there are internal stresses, the piece is likely to（可能） deform. Pieces that will warp severely while being heated have been seen, yet （然而）the heat-treater
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当是否内应力会引起翘曲的怀疑存在时，
可以通过将工件加工至1100然后进行冷却来验证。如果存在内应力，工件会发生变形。经过热处理的工件像我们看到的那样会发生严重的翘曲，但是我们仍然希望工件被扔到热处理炉中被处理，这样好过它存在内应力的状态。
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was expected to put them through and bring them out better than they were in the first place.
Welding
The maximum carbon content of 焊接
不需要预热或之后进行热处理就能安全焊接的最高碳含量为0.3％。高碳钢通过合适的plain carbon steel safe for welding without preheating or subsequent heat treatment is 0.3%. higher-carbon steel is welded every day, but only with proper preheating. There are two important factors: the amount of heats that is put in ; the rate at which it is removed.
Welding at a slower rate puts in more heat and heats a large volume of metal, so the cooling rate due to loss of heat to the base metal is decreased(减少). A preheat will do the same thing. For example, sae4150 steel, preheated to 600 or 800, can be
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预热通常也可焊接。有两点值得注意：吸收热量的多少；移除速度。
低速焊接带来了更多的热量，这对金属的大量体积进行了加热，所以冷却速度降低。预
热可以取得与之相当的效果。例如当 被预
热至 或 时可以很好的焊接。
由于周围金属的较高温度，当焊接弧移开焊接点后，冷却速度不会太快，产生了低速冷却的结果。即使是冷作硬化速度最快的金属也可以通过预热和慢速焊接达到良好的焊接效果。
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