QA问答：如果钻石是最硬的材料，我们为什么不用钻石做防弹背心呢？
If diamond is the hardest material, why don''t we make bulletproof vests out of diamond?
译文简介
网友：钻石是最硬的材料，如果你用它沿着一片玻璃划一道线，你就可以沿着这条划的线将玻璃折断。但是，如果你试着用锤子砸钻石。天哪，它会碎掉，因为它真的，真的很脆。现在想象一下用子弹打它（钻石）会怎么样.
正文翻译
If diamond is the hardest material, why don't we make bulletproof vests out of diamond?
如果钻石是最硬的材料，我们为什么不用钻石做防弹背心呢？
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Well, mainly because they’d be fucking rubbish.
Yes, diamond is the hardest material. That’s great if you want to drag it along a sheet of glass so you can snap it cleanly along the score line.
However, try hitting it with a hammer. Oh dear, it shattered, because it’s really, really brittle. Now imagine hitting it with a bullet.
主要是因为他们都很垃圾。
是的，钻石是最硬的材料，如果你用它沿着一片玻璃划一道线，你就可以沿着这条划的线将玻璃折断。
但是，如果你试着用锤子砸钻石。天哪，它会碎掉，因为它真的，真的很脆。现在想象一下用子弹打它（钻石）会怎么样。
I hit a sheet of clingfilm (saranwrap in the US?) and a sheet of glass with a hammer. The glass shattered but the clingfilm was ok. Therefore clingfilm is tougher than glass so why aren't car windscreens and phone screens made of clingfilm?
* This is not a serious question.
我用锤子敲了一块保鲜膜（美国的saranwrap？）和一块玻璃。玻璃碎了，但保鲜膜还是好的。
因此，保鲜膜比玻璃更坚固，那么为什么汽车挡风玻璃和手机屏幕不是由保鲜膜制成的呢？
这不是一个严谨的问题。
Because you’re asking a different question?
(Which you probably know)
Hard and Tough are measures of different things.
Diamonds are hard but not very tough.
Rubber is tough but not very hard.
因为你问了一个不同的问题？
（你可能知道）
“硬度”和“韧性”是衡量不同事物的标准。
钻石很硬，但韧性不足。
橡胶很有韧性，但硬度不够。
The rubber windshield never really got an industry foothold. The inventor didn't have a broad vision for his product.
橡胶挡风玻璃从未真正在行业中站稳脚跟，用橡胶做成的产品没有开阔的视野。
I don’t trust the rubber windshield companies. There’s a distinct lack of transparency.
我不相信那些做橡胶挡风玻璃的公司，显然做出来的产品缺乏透明度。
Well they sort of are … in your car windscreen between two sheets of glass is a transparent plastic layer. The glass is hard and the plastic tough. The combination is both.
在你的汽车挡风玻璃的两层玻璃之间是一层透明的塑料层。玻璃很硬，塑料很坚韧。两者的结合。
Very true. It’s laminated glass.
的确如此，这是夹层玻璃。
Actually it is a very serious question. Beyond the ‘because they don’t work’ answer lies an entire science of materials and their applications.
事实上，这是一个非常严肃的问题。除了“因为它们不起作用”这个答案之外，这其中还涉及到一门关于材料及其应用的完整科学。
I remember at school when we were taught the issue of hardness, toughness and other attributes of materials.
我记得在学校里，老师教我们硬度、韧性还有其他一些材料的属性。
When I was at school, the issue of hardness and toughness came down to how hard you could punch someone in the face, and how much you could take the punch.
I think things have probably moved on
当我还在学校的时候，硬度和韧性的问题归结为你能把一个人的脸打的多狠，以及你能承受多大的打击。我想事情可能已经发生了变化
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By the time I left high school, I had dropped back down to fights per week, and death threats received per month.
I think I’m now down to about a fight per month and death threats per year.
到我高中毕业的时候，我每周都在打架，每个月都收到死亡威胁。
我想我现在每个月都有一场打架，每年都有死亡威胁。
Interestingly, a much softer form of carbon (carbon fiber) can be used as a component of armor because of its flexibility and tensile strength.
有趣的是，一种更柔软的碳（碳纤维）可以作为盔甲的组成部分，因为它有很高的柔韧性和抗拉强度。
Or mix it with a lot of iron and make high carbon steel. Tough. Bullet proof. Recyclable.
或者把它和大量的铁混合，制成高碳钢，很坚固，防弹，也可以回收利用。
Heavy, though. Prone to rusting as well without treatment.
In F1, the chassis, bodywork and even the whole survival cell is made from Carbon Fibre. Hell, so are the drivers’ helmets!
不过，这应该很重，不经过处理也容易生锈。
在F1中，底盘、车身甚至整个零部件单元都是由碳纤维制成的。
司机的头盔也是一样！
That is why we have steel alloys like Corten and Stainless steel.
Most driver helmets are actually made from fiberglass and epoxy or polycarbonate. You really do not want the latter except when doing BMX or another bicycle related sports as they are very bad at protection with high speeds. Practically every bicycle helmet is made from polycarbonate and will give absolutely zero protection against a speeding car. There is no use for them in normal life except to look extremely stupid.
这就是为什么我们有耐候钢和不锈钢等合金钢。
大多数驾驶员头盔实际上是由玻璃纤维和环氧树脂或聚碳酸酯制成的。你真的不会想要后者，除非做BMX或其他与自行车相关的运动，因为他们在高速时保护能力很差。几乎每一个自行车头盔都是由聚碳酸酯制成的，对于超速的汽车完全没有任何保护作用。在正常生活中，他们除了看起来极其愚蠢之外没有任何用处。
Umm, one prent vest material includes ceramic, which shatters when hit by a bullet.
The problem with diamond is the fact that it WOULDN’T shatter, which would impart the impact of the bullet into the user, even if the bullet didn’t penetrate. It would likely cause an internal hemorrhage, possibly fatal.
一种流行的背心材料是陶瓷，被子弹击中会碎。钻石的问题在于它不会破碎，这将会将子弹的冲击力传递给使用者，即使子弹没有穿透，可能会引起内出血，甚至致命。
Body armour plates have ceramic layers, which absorb energy by crushing. Those are alternated with layers of polymer or metal, which deform and hold the thing together. A pure ceramic plate would just disintegrate and let the bullet through. So would diamond. A bullet will easily shatter diamond.
防弹衣有陶瓷层，通过粉碎吸收能量。它们与聚合物或金属层交替使用，这些聚合物或金属层会变形并将物体固定在一起。一个纯陶瓷板会解体，让子弹穿过。钻石也是如此，子弹能够轻易地粉碎钻石。
Right, it absolutely would. That doesn’t mean that it will be able to penetrate skin beneath that layer of diamond on the first shot. The first shot would shatter it, but it would likely take a follow up shot to do any damage. It’s brittle but has a high yield strength, so until it’s already shattered, it would provide good protection.
是的，绝对会。这并不意味着它能在第一次射击时穿透钻石层下面的皮肤。第一枪会把它击碎，但可能要再开一枪才能造成伤害。钻石很脆，但有很高的屈服强度，所以在它破碎之前，它可以提供很好的保护。
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It depends. If it hit a sheet of diamond, you may get away with a single strike without significant injury. It’s brittle, but that first impact would not be as easy as breaking it with a hammer. It would be as easy as hitting it with a hammer and expecting that hammerhead to make contact with the ground below it on the first blow—just not going to happen until you first shatter it.
If you had armor made of thousands of diamonds embedded in a normal cloth material, yes, the bullet would probably transfer enough of it’s momentum to be akin to just striking you directly. If you had a sheet of it, though, that momentum is going to spread out and dissipate in all directions and as I suggest, you might end up being okay for one shot.
视情况而定，如果击中了一块钻石，你可能只命中一击而不会受重伤。钻石很脆，但第一次撞击不会像用锤子那样容易打碎它。这就好像用锤子击打它，并期望锤头在第一次击打时就能接触到地面一样简单——但在你第一次击碎它之前，这是不可能发生的。
如果你的盔甲是由数千颗钻石镶嵌在一个普通的布料材料中，是的，子弹可能会转移足够的动量，就像直接击中你一样。但如果你有一张纸，动量会向四面八方扩散消散，就像我建议的那样，你可能会在一次射击中就结束生命。
So being shot while wearing diamond body armour would result in one bullet would and probably dozens of diamond shrapnel wounds? It sounds only marginally better than wearing body armour made from live landmines.
所以穿着钻石防弹衣中枪只会造成一颗子弹可能还有几十处钻石弹片伤？这听起来只比穿着用地雷制成的防弹衣好一点点。
And as someone else stated, they burn. First thing British troops in Northern Ireland were told was “Do NOT do up the zip on a flak jacket”. Nylon also melts, and makes it impossible to remove in the event of being hit by a petrol bomb.
就像其他人说的，他们会燃烧。在北爱尔兰的英国军队被告知的第一件事是“不要把防弹衣的拉链拉上”。尼龙也会融化，这使得它在被汽油弹击中时无法被移除。
To be fair, nylon burns a lot more easily than diamonds.
公平地说，尼龙比钻石更容易燃烧。
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The prime reason that Velcro fastenings made an appearance in the 1970s.
这就是维可牢尼龙搭扣（是由瑞士发明家乔治发明的）在20世纪70年代出现的主要原因。
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Ceramics behave in the same manner, yet they are part of the most advanced types of passive armor. You are completely right about the fact that diamond by itself would suck as armor, but it may be part of a relatively efficient armor system (though probably not efficient from a price perspective).
陶瓷也是如此，但它们是最先进的盔甲的一部分。你说的完全正确，钻石本身作为盔甲就很糟糕，但它可能是相对有效的盔甲系统的一部分（尽管从价格角度来看可能并不有效）。
my diamond bulletproof vest is fireproof but it cost $4 million. My wife is very angry with me for buying it.
我的钻石防弹背心是防火的，但它花了我四百万美元。我妻子因为我买了它而对我很生气。
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Diamonds are carbon, they are not fire-proof.
钻石是碳元素组成的，它们不耐火。
At 763 degrees Celsius, sure diamonds will burn.
在763摄氏度，钻石肯定会燃烧。
There is a very noticeable difference between “hard” and “strong.”
“硬”和“强”之间有一个非常明显的区别。
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At least when you die you have a way to pay for the funeral.
至少当你死的时候你有办法支付葬礼的费用。
Diamond is not even a metal. It’s carbon…
钻石甚至不是金属，它是碳…
Yes, I know.
是的，我明白。
I guess technically, Lonsdaleite is a diamond with a different crystalline structure, but someone chose to give it a different name. But it is generally half again as “strong” as diamond.
我想从技术上讲，Lonsdaleite是一种晶体结构不同的钻石，但有人给它取了个不同的名字。但一般来说，它的“强度”是钻石的一半。
Besides, it is going to be very very expensive.
而且，它非常非常的贵。
Did the OP say diamond is the hardest METAL?
钻石是最硬的金属吗？
Well, to astronomers, everything above helium in the table of elements is called a metal.
对天文学家来说，元素表里除氦以外的一切都被称为金属
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Using a hammer will chip (not break) a quality diamond. A chipped diamond can be fixed.
使用锤子会使高质量的钻石碎裂（而不是折断），脱落的钻石可以修复。
Slightly "off topic", but apparently when Tsar Nicholas and his family were murdered in 1918, some of his daughters didn't die in the fusillade of bullets, as they'd stitched the families jewellery into their underclothes. This deflected the bullets and they had to be finished off with bayonets!
虽然有点跑题，但很明显，当沙皇尼古拉斯和他的家人在1918年被谋杀时，他的一些女儿并没有死于枪林弹雨下，因为她们把家族的珠宝缝进了她们的内衣里。这使子弹偏离了方向，他们不得不用刺刀来干掉他们！
The way I saw it explained (in a YouTube video, no less), which helped, was via an analogy:
You can make a mark on wood by scratching it with glass. So glass is harder than wood.
However, you can break a glass window by hitting it with a wooden baseball bat. So glass is more brittle than wood.
通过一个类比，我看到了一个很有帮助的解释（至少是在YouTube视频中）:
你可以用玻璃在木头上划个记号，所以玻璃比木头硬。
然而，你可以用木制棒球棒击碎玻璃窗，所以玻璃比木头更易碎。
That’s why a diamond cutter needs nerves of steel. Cut a diamond in the wrong place and it will shatter ruining its value.
这就是为什么钻石切割师需要钢铁般的意志。因为钻石切错了地方就会破碎，失去价值。
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There is a great misunderstanding between harness and toughness. Diamonds are very hard, but they're not very tough, meaning they cannot absorb a lot of energy before fracture. Contrast that to ballistic fibers which are considerably more tough, and enhanced moreso by the weave of the fabric, allowing for even more energy absorption. In most applications, it's not one singular property that makes a material most suitable, but a balance of many.
硬度和韧性之间存在很大的误解。钻石很硬，但没有韧性，这意味着它们在受到冲击时不能吸收大量能量。相比之下，弹道纤维是相当坚韧，并通过编制这种纤维使其更加具有韧性，能够吸收更多的能量。在大多数应用中，选用合适的材料并不是看它的单一属性，而是多种属性的平衡。
Imagine how much a vest made of diamond would weigh, it be like wearing a boat anchor around.
想象一下，一件钻石做的背心有多重，它就像戴着一个船锚一样。
Its a crystal. Crystals have natural fracture lines. If hit at the right angle they will split.
它是晶体，晶体有天然的断裂线，如果以正确的角度撞击，它们会分裂。
One diamond bullet proof vest is worth more than all your internal organs
一件钻石防弹背心比你所有的内脏都值钱
Thats like asking why dont we make electrical wire out of gold since its a better conductor than copper? Well simply because its way too expensive.
这就像问为什么我们不用金做电线，因为金的导体比铜好？很简单，因为它太贵了。
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Diamond is not a metal.
钻石不是金属。
Diamond is not a metal.
钻石不是金属。
Because hardness isn't nearly as important as toughness and strength when it comes to something like a bulletproof vest. Hardness is an obxt's ability to resist scratches and similar damage. Toughness is an obxt's ability to deform without breaking. Strength is an obxt's ability to resist deforming in the first place.
It's much more important that a bulletproof vest minimizes deformations and absolutely doesn't fracture what hit by a bullet
因为对于防弹背心这样的东西来说，硬度远不如韧性和强度那么重要。硬度是物体抵抗划痕和类似损伤的能力。韧性是一个物体变形而不折断的能力。强度首先是物体抵抗变形的能力。
更重要的是，一件防弹背心能最大限度地减少变形，而且绝对不会让子弹击中的物体破碎。
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Diamond is not a metal!!!
its carbon crystal
carbon is not a metal
钻石不是金属！！
它是碳晶体
碳不是金属
are you sure? It is difficult to break a diamond
你确定吗？钻石是很难打碎的
First, diamond is not a metal. It is crystallized carbon.
Second, you are misunderstanding the concept of “hardness”. It merely means the ability to cut or scratch other materials. Diamond can cut all other known substances, thus it is the “hardest” natural material known. Diamonds are crystals, and are actually pretty tough, but while not overly brittle they can be crushed or shattered. They will withstand a lot of shock treatment if flawless, but they can be easily smashed with a tack hammer. At the same time they are many times harder than the hammer’s metal.
Even if crystallized carbon, diamond, could be formed into the shape of a vest, or if a vest could be made of thousands of diamond crystals, the shock of a bullet striking it would smash it into a thousand shards. It would offer almost no resistance to a bullet, much less than plate glass. Therefore, a vest of diamond would be a very expensive but utterly impractical idea.
首先，钻石不是金属，它是结晶碳。
第二，你误解了“硬度”的概念。它仅仅意味着切割或刮伤其他材料的能力。钻石能切割其他所有已知物质，因此它是已知的“最硬”的天然物质。钻石是晶体，实际上非常坚硬，但虽然不是太脆，它们也可以被压碎或粉碎。如果要把钻石做的完美无瑕，它们将经受住大量的电击处理，但它们很容易被钉锤砸碎。同时，它们要比金属做的锤子坚硬许多倍。
即使钻石是碳化结晶，但可以做成一件背心的形状，或者如果一件背心可以由成千上万的钻石晶体制成，子弹击中它的冲击波会把它击成碎片。它对子弹的抵抗力几乎为零，比平板玻璃小得多。因此，一件钻石背心将是一个非常昂贵但完全不切实际的想法。
Diamond isn't a metal and bulletproof vests aren't either.
Even if you would make a bulletproof vest from diamond it would shatter. Diamond is hard but VERY weak and brittle, like stale bread.
钻石不是金属，防弹背心也不是。
即使你用钻石做防弹背心，它也会被击的粉碎。钻石很硬，但很脆易碎，就像不新鲜的面包。
Imagine you have a glass in your hand, you can easily crush it with your hand but shards are hard enough to cut your skin. The deal with the Diamond is somewhat same. It can shatter rather easily but it's hard enough to cut through any other material.
想象一下，你手里拿着一个玻璃杯，你可以很容易地用手捏碎它，但碎片的硬度足以划破你的皮肤。钻石也一样，它可以很容易地被打的粉碎，但它的硬度足以穿透任何其他材料。
The salient point of a vest is to absorb impact and dissipate energy. Diamonds would transfer that energy rather than absorb it. I’ll stick with Kevlar.
背心的重点是吸收冲击和消散能量。钻石会转移而不是吸收能量。我还是用凯夫拉纤维吧。
A diamond is one of the hardest known substances. ... A bullet can easily shatter a diamond. A bullet would have more trouble shattering your arm than a diamond (unless it was a very big diamond. Then it might stop a bullet.
钻石是已知最坚硬的物质之一....子弹可以轻易地打碎钻石。相比一颗子弹，一颗钻石更容易打碎你的手臂（除非是一颗非常大的钻石）。那它可能会挡住子弹。
If diamond is the hardest metal, why don't we make bulletproof vests out of diamond?
There is already diamond bulletproof vests (DBPV). Its just very expensive, $2.8 million - $3.2 million, so its not practical when there are bulletproof vests for cheaper. The DBPV is encrusted with 880 black diamonds and its carat weight is over 140.
如果钻石是最硬的金属，我们为什么不用钻石做防弹背心呢？
已经有了钻石防弹衣。只是价格很贵，280万到320万美元，所以当有更便宜的防弹背心时，这种钻石防弹背心是不实用的。DBPV镶嵌着880颗黑钻，其重量超过140克拉。
Diamonds are hardest element so it can scratch or cut into other elements.
It can not take impact - a soft hit with a hammer will shatter a diamond.
Same will happen with a bullet.
Also - bullet proof vest with diamonds will cost a lot…..
钻石是最坚硬的物质，所以它可以划伤或切割其他材料。
它不能承受冲击——用锤子轻击会粉碎钻石。
同样，用子弹击中钻石，钻石也会粉碎。
另外——用钻石做防弹背心会花费很多钱.....
Diamond is a rare material and a very expensive one at that you can imagine how much would It take just to make one vest thick enough for use
钻石是一种稀有的材料，也是一种非常昂贵的材料，你可以想象仅仅做一件足够厚的背心需要多少钱
Diamond isn’t metal.
diamond is hard, relative to other material, but its also brittle. Brittle doesn’t make good shielding.
钻石不是金属。
与其他材料相比，钻石很硬，但也很脆。脆性材料在防护方面并不突出。
Diamond is not the hardest metal. It is not even a metal being composed entirely of carbon (the same stuff in a pencil).
The hardness here is inability to be scratched by another substance. It does not define tensile strength or other common understandings of what it means to be hard.
If such a thing was made of diamond and hit by a bullet it would shatter into tiny pieces.
Better using kevlar or ceramics as bulletproofing.
钻石不是最硬的金属。它甚至不是一种完全由碳组成的金属（铅笔里也含有碳）。
这里的硬度是指不能被其他物质划伤。它没有定义抗拉强度或其他关于硬度的常见理解。
如果这种东西是由钻石制成的，然后被子弹击中，它就会碎成小碎片。
最好是用凯夫拉纤维或陶瓷做防弹材料。
Diamond isn't a metal first of all.
It is very expensive though. Millions of dollars per vest. Not very cost efficient.
首先，钻石不是金属。
不过它很贵，每件背心价值数百万美元，不是很划算。
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Being strong and being hard are two different qualities. Diamond is hard because no other material can make a scratch on it. Diamond is not strong. A 5 year old child can break it with a hammer.
强度和硬度是两种不同的属性。钻石之所以坚硬，是因为没有其他材料能在它上面留下划痕。钻石比较脆，一个5岁的孩子可以用锤子把它敲碎。
why diamond is not used for making bulletproof vests.
Brittle. Yes, diamond even though hard, is brittle. It shatters like glass on hard impact.
Cost and availability. We don't want to use a material which is costly and not available in huge quantities. Even if diamond could absorb bullet impact, tye cost and availability would prohibit its use for the above said purpose.
为什么钻石不能用来做防弹背心。
因为很脆，是的，钻石虽然硬，但很脆。它会像玻璃一样被撞得粉碎。
成本高和可用性低，我们不想使用那种既昂贵又得不到大量供应的材料。即使钻石可以吸收子弹的冲击，但其成本和可用性将限制其使用。
A bulletproof vest has to absorb energy. Hard substances are brittle. They absorb little energy until they break. If you want to absorb energy you need something tough.
防弹背心需要吸收能量，硬物质易碎。它们只吸收很少的能量，直到它们破碎。如果你想吸收能量，你需要一些坚韧的材料。
In short, hardness is not a particularly desirable property in armour. Glass is one of the hardest ‘everyday’ substances, and it certainly wouldn’t be your first choice for making armour out of.
You want strength (tensile in particular) combined with ductility, so that the armour can absorb the energy of the impact. Diamonds are not especially strong, and are very brittle - so even if you could make a sheet of the stuff, it would be hopeless as armour.
简而言之，硬度并不是盔甲特别需要的特性。玻璃是最硬的“日常”物质之一，它当然不会是你制作盔甲的首选。
你需要强度（特别是拉伸）与延展性相结合，这样盔甲就可以吸收冲击的能量。钻石不是特别坚固，而且非常易碎——所以即使你能制作一张钻石的薄片，它也无法做成盔甲。
It is very difficult to make diamond. Imagine a large sheet of diamonds. Impossible for actual technologies. And if you are thinking about glueing several diamonds, you move the problem on glue, so the diamonds are useless.
制造钻石是很困难的，想象一下制造一大片钻石，在实际技术中是不可能实现的。如果你想把几个钻石粘在一起，你就把问题转移到了胶水上，这样钻石就不起作用了。
Bulletproof vests need a high tensile strength material that acts like a tiny stretching net. Diamond is a solid brittle carbon crystal. Kevlar is a synthetic weave that does have those properties.
As a common lead bullet hits a Kevlar vest, the bullet deforms and goes splat on the Kevlar weave. This spreads the bullet’s force out along the weave and keeps it from piercing the body.
防弹背心需要一种高抗拉强度的材料，这种材料的作用就像一个微小的伸缩网。
钻石是一种固体脆碳晶体，凯夫拉纤维是一种具有这些特性的合成纤维。
当一颗普通的铅弹击中凯夫拉纤维背心时，子弹变形并飞溅到凯夫拉纤维上。这样子弹的力量就会沿着织物扩散，从而避免穿透身体。
It’s hard but it’s also brittle. It’s not going to stand up to a big shock.
Take a diamond, stick it on an anvil and hit it with a sledgehammer. You’ll get diamond dust in the process. The best bulletproof vests are the ones that are strong but flexible.
钻石很硬，但也很脆。它经受不住大的冲击。
拿一颗钻石，把它钉在铁砧上，用大锤砸它。在这个过程中你会得到钻石粉。最好的防弹背心材料是那些既结实又柔韧的材料。
Diamond is the hardest material as the composition of the diamond is about 99.95 percent carbon. The other 0.05 percent can include one or more trace elements, which are atoms that are not part of the diamond's essential chemistry. Considering the point of making a bulletproof vest from the diamond, the economic factors are responsible because as compared to the polyethylene fibers diamond is highly expensive and the high production cost will not make it economically feasible.
钻石是最坚硬的材料，因为钻石的成分大约有99.95%是碳。剩下的0.05%可能包括一种或多种微量元素，它们是不属于钻石基本化学成分的原子。考虑到用钻石制作防弹背心的观点，经济是主要的影响因素，因为与聚乙烯纤维相比，钻石非常昂贵，生产成本高，在经济上是不可行的。
Hardness - ability of a material to resist plastic deformation OR a materials ability to resist indentation.
Toughness - ability of a material to absorb energy and plastically deform without fracturing.
As one can see, hardness is not the same as toughness and typically they are terms used interchangeably in everyday life. You want bulletproof material to be tough, not hard. Hence, diamond bulletproof vest would be a pretty terrible idea.
硬度-材料抵抗塑性变形或材料抵抗压痕的能力。
韧性-材料吸收能量和塑性变形而不断裂的能力。
正如我们所看到的，硬度和韧性是不一样的，通常它们在日常生活中可以互换使用。你希望防弹材料是坚韧的，而不是坚硬的。因此，钻石防弹背心将是一个非常糟糕的主意。
A diamond is not metal and not only would it be financially prohibitive to make a vest out of this material.
钻石不是金属，而且用这种材料做背心不仅会在经济上令人望而却步。
Diamond is not a metal.
Diamond is a STONE, crystal.
钻石不是金属。
钻石是一种石头、结晶。
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处
Originally Answered: If diamond is the hardest metal, why don't we make bulletproof vests out of diamond?
Diamond is brittle like glass, and isn’t a metal. I really wish that people were more educated.
如果钻石是最硬的金属，我们为什么不用钻石做防弹背心呢？
钻石像玻璃一样易碎，而且不是金属。我真的希望人们能接受更多的教育。
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处