听力课堂TED音频栏目主要包括TED演讲的音频MP3及中英双语文稿，供各位英语爱好者学习使用。本文主要内容为演讲MP3+双语文稿:摩擦学及其对我们生活的惊人影响，希望你会喜欢！

【演讲者及介绍】Jennifer Vail

Jennifer Vail结合了机械工程和材料科学来研究相对运动中的相互作用表面。

【演讲主题】摩擦学及其对我们生活的惊人影响

The science of friction -- and its surprising impact on our lives

【中英文字幕】

翻译者Isabel Z 校对者 Yanyan Hong

00:19

I have to admit that it's a lot of fun when people ask me what I do for my job, because I tell them I literally rub things together. This sounds ridiculous, just rubbing things together.

当人们问我做什么工作时， 我得承认答案很有趣。 因为我告诉他们， 我就是拿物品相互摩擦。 只是拿东西相互摩擦， 听起来很荒唐。

00:31

But it has a technical name: tribology. T-r-i-b-o-l-o-g-y, from the ancient Greek word "tribos," which means "to rub." It's a funny-sounding word you've probably never heard before, but I promise you, discovering it changes your experience with the physical world. Tribology has given me amazing projects. I've worked on materials that fly, and I've worked on dog food -- a combination that doesn't sound like one person has any business doing in the span of just a couple years, until you start to view the world through a tribological lens. And I think you'll be surprised at how significant a little bit of tribology can be in alleviating some very large problems.

但是它有一个技术别称： 摩擦学。 T-r-i-b-o-l-o-g-y， 源自古希腊语：“tribos”， 意思是“摩擦”。 你可能从来没听过 这个有些好笑的词， 但是我向你保证， 探索它，将会改变 你对物质世界的体验。 摩擦学给了我机会去 从事许多很棒的项目。 我研究过飞行器材料， 也研究过狗粮—— 除非你开始以摩擦学的 眼光来看这个世界， 不然这组合 一般人很难 在几年内同时接触到。 我想你们会惊讶于 一点摩擦学在解决难题上的 重要性。

01:17

Tribology is the study of friction, wear and lubrication. You have all experienced all three of these things. Remember the last time you tried to move a heavy object across the floor, and you could just feel something resisting you? That would be friction. Friction is the force that opposes motion. Wear is the loss or transfer of material. It's the reason you have to replace your favorite shoes, because eventually the soles disappear. Lubricants are used to reduce friction and wear. They loosen up those stubborn rusted bolts that just otherwise will not budge.

摩擦学是研究摩擦力、 磨损和润滑的学科。 你们都体验过这三个东西。 还记得上一次你试着 在地板上移动重物的时候， 你能够感觉到 有东西在阻止你吗？ 那就是摩擦力。 摩擦力是阻碍运动的力。 磨损则是指物质的损耗和转移。 再喜欢的鞋子，鞋底终究 会因磨损殆尽而被淘汰。 润滑剂能用来减少摩擦和磨损。 它们能松开那些生锈卡死， 难以转动的螺栓，

01:51

But tribology is also defined as the science of interacting surfaces in relative motion. So, interacting surfaces in relative motion: there are a lot of those in the world. As you're sitting there right now, are you wiggling your foot at all or maybe shifting around in your seat? Because guess what? Tribology is happening. Even the smallest shift in your seat involves two surfaces moving relative to each other. And your tribological interaction for the shift will be different than the person next to you. This is because the clothes you're wearing change the friction between you and the seat. If you're wearing silk, it's a little easier to squirm around in the seat than if you're wearing wool. That's because the friction is lower for silk.

但是摩擦学也被定义为 在相对运动中， 表面相互作用的学科。 所以，相对运动中的表面相互作用： 世界上有很多这样的例子。 你现在坐在这里， 是不是在活动你的双脚， 或者不断改变你的坐姿。 因为摩擦学正在起作用。 即使你只是在椅子上稍稍挪动， 都涉及了两个相对运动的表面。 并且你移动的摩擦作用 会与你身边的人有所不同。 这是因为你所穿的衣服 改变了你和座椅之间的摩擦力。 如果你穿了丝绸，会比你穿羊毛时 在座位上扭动更容易一些。 这是因为丝绸的摩擦力小一些。

02:35

If you're moving your ankle or wiggling your ankle at all, did it make a popping sound? You've had that, right? You get up, you move around, and some joint cracks or pops. Thank you for that sound, tribology. That sound can come from the fluid that lubricates your joints just moving around. You're essentially releasing gas bubbles in that fluid. That sound can also come from the tendons simply moving over each other. Pretty common in the ankle, so any of my fellow foot-wigglers out there may suddenly find themselves curious about the tribology of tendons.

你在移动或者扭动脚踝的时候， 是不是有发出“咔咔”声？ 你经历过的，对吧？ 你起床，走动， 一些关节碰撞发声， 这都是因为摩擦学。 这种声音可能是由于 润滑关节的液体。液体中的气泡被释放所导致的。 这种声音也可以来自于 肌腱之间的相互移动， 在脚踝处很常见， 所以我那些喜欢 扭动脚踝的朋友， 会突然对肌腱之间的 摩擦学感到好奇。

03:08

But how does one become a tribologist like me? It starts when you're a kid, of course. I was a ballerina growing up. I reached the level where I was dancing on my toes, or "en pointe." Now, when you're dancing en pointe, you're wearing those amazing shoes, but they can be slippery on the stage. The last thing you want to do when you're trying to dance on your toes is to slip and fall. So we had boxes of stuff called rosin. We would step into the rosin, put a light coating on our shoes. Rosin comes from tree sap and, in its powdered form, makes things less slippery. You learned real fast as a dancer how much was the right amount to put on your shoes, because if you didn't put enough on, you were probably going to slip due to the low friction between your shoe and the stage. Best case scenario, you're the clumsy ballerina on stage, but the worst case scenario would be an injury. Already, I was optimizing and manipulating friction. You see, I was destined to be a tribologist.

但我又是如何成为摩擦学家的呢？ 当然，这得从小时候说起。 我跳着芭蕾舞长大。 我可以踮着脚尖起舞， 法语里叫 “足尖舞 (en pointe)”。 当你踮着脚尖跳舞时， 你会穿着那漂亮的舞鞋， 但是它们可能会 让你在舞台上打滑。 当你跳舞的时候，最可怕的 莫过于滑倒。 所以我们会用一种叫松香的东西。 我们踩进松香里， 舞鞋上就会有一层薄膜。 松香来自于树液， 粉末状的松香可以防滑。 作为一个舞者，你会很快知道 应该放多少松香在舞鞋上。 因为如果没有放够， 你很可能滑倒， 因为你的鞋子和舞台之间 没有足够的摩擦力。 幸运的话， 你只是在舞台上 看起来手脚不协调， 但要是运气不好，你就会受伤。 那个时候，我已经在 优化和控制摩擦力了。 你们看，我注定 要成为一个摩擦学家。

04:08

(Laughter)

（笑声）

04:10

But you were also a junior tribologist. When you used crayons or colored pencils, you knew that the harder you pressed, the darker the color. You also knew this meant you were going to have to sharpen that crayon or colored pencil more frequently, because it was wearing down faster.

但是你们也是 初级的摩擦学家： 当你使用蜡笔和彩铅的时候， 你知道你用的力气越大， 颜色就会越深。 你也知道这意味着 你要更加频繁地削笔， 因为它们会更快地磨光。

04:26

Now let's talk about those enticing shiny waxed floors that you just had to slide across. You knew if you put on a pair of socks, you were going to get a really good slide across that floor. Good luck trying to do that barefoot. Master manipulators of friction.

现在让我们来谈谈 那些闪亮的打蜡地板， 人人都想在上面滑来滑去。 大家都知道如果穿双袜子， 滑动起来更加容易。 赤脚可就没那么轻松了。 多么高明的摩擦力操纵技巧。

04:44

All kids are tribologists. What about us as adults? At some point today, you brushed your teeth. I hope.

孩子们都是摩擦学家。 那么大人呢？ 各位今天都刷过牙了， 但愿如此。

04:52

(Laughter)

（笑声）

04:54

This is tribology in action. The toothpaste and toothbrush are working to remove or wear the plaque from your teeth. For the record, my dad is a dentist. Never thought my career was going to circle back to the family business. But one day, we found ourselves speaking the same language when I was tasked with developing a test to investigate plaque removal. Sounded simple enough, until I started to look at it as a tribologist, and then it became incredibly complex. You have hard materials -- those would be your teeth -- soft materials like your gums, the toothpaste, the toothbrush. There's lubrication -- the form of saliva and water -- the dynamics of the person doing the brushing and more. I promise if we put diamonds in your toothpaste, you're going to remove that plaque. Probably going to remove your teeth as well. So there's a fine balance to be had between wearing the plaque away and not damaging your teeth and gums.

这就是摩擦学的作用。 牙膏和牙刷的作用 是清除或磨掉 你牙齿上的污渍。 郑重声明，我爸爸是牙医。 我从来没有想过 自己会追随他的脚步。 但是有一天我们发现 我们说着相同的话， 当时我刚接受了 开发牙渍去除测试的任务。 听起来很简单， 直到我开始 以摩擦学家的角度看待它， 才发现它非常复杂。 其中涉及到坚硬的材料—— 这就是你的牙齿； 软的材料—— 就像你的牙龈，牙膏和牙刷； 润滑物——像是唾液和清水； 还有人们刷牙的动作，等等。 我保证如果我们在你的 牙膏里添加钻石， 牙渍便可以去除， 很可能还会连你的牙齿一起磨掉。 所以需要一个去掉牙斑 又不伤害牙齿牙龈的 折衷方法。

05:48

We're brushing our teeth because we ate. Eating is another routine thing we all do. Seems simple enough. But it's another field of tribology, and it's not so simple. You have the food, which will break and wear while you're eating, and that food is interacting with your teeth, your tongue, your saliva, your throat. And all of those interactions are going to influence your experience of eating. I think you can all recall a moment where you tried something new and you just found yourself going, "Well, it tastes alright. I really don't like that texture." Tribologists are looking at lubricity, the coefficient of friction, as ways to connect mouth feel and texture to what you're experiencing, so that if we're changing the formulations of what we're eating and drinking so the sugar content or fat content are different, how does that change mouth feel? How do we quantify that? This is what tribologists are looking to solve. And while my colleagues were in one corner of this lab looking at the fat content of yogurt, I was in another corner studying dog food. That lab smelled really good, by the way, let me tell you.

我们刷牙是因为我们要吃东西。 吃东西是我们另一个日常所需， 看起来很简单， 但它是摩擦学的另一个领域， 并没有那么容易。 你吃东西的时候， 食物会被破坏和分解。 这些食物和你的牙齿， 舌头，唾液和喉咙 相互作用。 所有的这些作用都会 影响你的进食体验。 我想你们都会想起 尝试新事物的时刻， 你会发现自己在想： （咀嚼声） “味道还行， 但我真的不喜欢这种口感。” 摩擦学家研究润滑和摩擦系数， 让你体验到的口感 和味道得以相辅相成， 所以当我们改变饮食配方， 不同的糖分含量或者脂肪含量， 口感会出现怎样的变化？ 我们将如何量化这个问题？ 这就是摩擦学家要解决的问题。 当我的同事 在实验室的一个角落 研究酸奶的糖分含量， 我在另外一个角落 研究狗粮。 顺便说一句， 那个实验室闻起来很香。

06:55

We all brush our teeth on a regular basis. How many of us brush our pets' teeth? Animals as adults commonly get periodontal disease, so we really should be brushing their teeth, and more pet owners are starting to do this. I know my best friend is really great at brushing her cat's teeth, somehow. Good luck trying to do that with my cat. So what pet food suppliers are trying to do is incorporate plaque removal in things like treats. If you have a dog, you may have observed that you give a dog a treat, and it magically seems to disappear after just one bite. So the added challenge here is: How do you remove plaque when you have one bite? I developed a benchtop test to study this problem, and to do so, I had to mimic the oral system of dogs: their teeth, plaque, saliva. And I used friction and wear measurements to study the effectiveness of that treat on removing plaque. If you're sitting there right now thinking about the last time you didn't brush your dog's teeth, you're very welcome.

我们都会有规律地刷牙， 但有几个人会给宠物刷牙？ 成年动物通常会患牙周病， 所以我们应该给它们刷牙。 越来越多的宠物主人 开始这样做了。 我知道我的好朋友 很擅长给她的猫咪刷牙。 我希望我也能这样。 宠物食品供应商正在尝试 研发能够去除牙斑的零食。 如果你有养狗， 你会发现喂狗吃零食， 它一口就能吞下去，很神奇。 所以更大的挑战在于： 如何在一口吃掉大餐的 情况下去除牙渍。 我开发了一个台式实验 来研究这个问题， 还模拟了狗的口腔： 包括它们的牙齿， 牙菌斑和唾液分布。 我用通过测量摩擦力和磨损程度 来研究餐食对去除牙菌斑的效果。 如果各位还在纠结 上次没给狗刷牙， 不用客气。

07:52

But what's the big deal with tribology? Let me give you one more example. No matter where you are right now, you got to this location somehow. Maybe you walked or rode your bike, but for most people in this room, you probably came in a car. Just think about all the tribological systems in a car. You have your personal interactions with the car, the car's interactions with the road and everything under the hood and in the drivetrain. Some routine maintenance is directly connected to tribology. You know how many miles your tires are recommended for using before you replace them. You regularly check the treads on those tires. You're actively monitoring the wear of your tires. Tribology is the study of wear and friction, and with tires, friction can be the difference between a safe arrival and a car accident. This is because the friction between your tires and the road will influence your acceleration, your deceleration and your stopping distance. As a driver, you instinctively already know how important friction is, because you know that when the roads are wet, they're more dangerous because they're slippery. This is because the water is reducing the friction between your tires and the road. You may recall that friction is the force that opposes motion, so water reducing that force means it's now easier for you to move, hence it's more slippery when the roads are wet.

但是摩擦学到底有多重要呢？ 再举一个例子， 不管你现在在哪里， 你总有办法到达这里。 有人走路或者骑车， 但是你们大多数人 应该是开车来的。 想想车里所有的摩擦系统。 你和车有相互作用， 车和马路之间也有， 以及引擎盖下和传动系统内的一切。 定期保养与摩擦学就息息相关， 各位都知道轮胎大概跑 多少路就需要 检查更换， 你也会规律地检查车胎胎面。 你其实就是在检查轮胎的磨损程度。 摩擦学研究的是磨损和摩擦力。 而对于轮胎，摩擦力 是旅途平安的关键。 因为轮胎和路面的摩擦力 影响着加速和减速， 以及刹车距离。 作为司机，你知道摩擦力的重要性。 因为你知道路面湿润时， 开车更危险，更容易打滑。 这是因为雨水降低了 轮胎和路面的摩擦力。 你们可能还记得， 摩擦力是阻碍运动的力， 所以雨水降低摩擦力 意味着移动更容易， 湿润的路面就会更滑。

09:12

Something else to consider is that overcoming friction takes energy, so you're losing energy to friction. This is one way your tires can influence your fuel efficiency. And, in fact, did you know that about one-third of the fuel that you put into your internal combustion engine vehicle will be spent overcoming friction? One-third.

另外还有一件事要考虑进去， 克服摩擦力需要能量， 所以摩擦会损耗能量。 这是轮胎影响燃油效率的一种方式。 你们知道，其实引擎中 三分之一的燃油都消耗在了 克服摩擦力上吗？ 三分之一。

09:33

Tribology research has helped us reduce friction and therefore increase fuel efficiency and reduce emissions. Holmberg and Erdemir have actually done some great studies showing the impact tribology research can have on reducing our energy consumption. And they found that, looking over the span of 20 years, we had the opportunity to reduce the energy consumption of passenger vehicles up to 60 percent. When you think about all the cars in the world, that's a lot of energy we can save. It's part of the nearly nine percent of our current global energy consumption that the authors identified tribology can help us save. That's a significant amount of energy. So when you look at the numbers, tribology can do some amazing things.

对摩擦学的研究 能帮助我们减少摩擦力， 从而提高燃料效率，减少排放。 霍尔姆伯格和埃尔德米尔 做了一些很棒的研究， 显示了摩擦学研究 对减少能源消耗的影响。 他们发现在过去的 20 年里， 我们本有机会减少 高达 60% 的 车辆能源消耗。 想想世界上的所有车辆， 我们其实可以节约很多能源。 作者认为，摩擦学可以 帮助我们节约目前 近 9% 的全球能源消耗中的一部分。 这是个庞大的数字。 只需要看看这些数据，就会发现 摩擦学多么了不起。

10:16

My colleagues have identified up to 20 quads of energy we can save across the US alone. To put this in perspective: one quad of energy is roughly equivalent to 180 million barrels of oil, and tribology can help us save 20 times that. This is through new materials, new lubricants, novel component design, doing things like making wind turbines more efficient and reliable. This happened just by putting 31 people in a room who viewed the world through a tribology lens. Imagine the opportunities that will reveal themselves as more of us start to see tribology all around.

我的同事已经发现，单单在美国， 我们就可以节约 20 多夸特的能源。 解释一下： 1 夸特大约相当于 1.8 亿桶石油。 而摩擦学可以帮助我们节省 相当于 20 倍这个数字的能量。 我们可以通过新的材料、 新的润滑剂， 以及新的组合设计， 来提高风力涡轮机的效率和可靠性。 只需将 31 个人放到一间屋子里， 以摩擦学的角度 来观察这个世界。 想象一下，随着越来越多的人 开始接触摩擦学， 这些机会将逐渐展现在我们面前，

10:53

My favorite projects right now are in aerospace applications. I love reducing wear and friction in these challenging environments. I can make materials and parts that will reduce the friction in moving components and engines so that they have less force opposing their motion. Less force to move means they require less power, so you can use a smaller actuator, which would weigh less, which saves fuel. I can also help make parts that last longer through lower wear. This will reduce material waste and also means we're manufacturing the parts less frequently, so we're saving energy in manufacturing.

我现在最喜欢的项目 是航天应用， 尝试在充满挑战的环境里 减少损耗和摩擦。 我可以制作能够减少 运动部件和引擎内部摩擦的 材料和零件， 以减少运动阻力。 摩擦力减小， 意味着所需的能量也更少， 可以使用更小， 更轻， 也更节能的驱动器。 我制作出的零件 因为磨损小也更加耐用。 这减少了材料浪费， 也意味着我们 制造零件的频率会降低， 从而节省了生产过程中 所消耗的能源。

11:29

I encourage you to start seeing tribology in the world around you and to think about how you would improve those interacting surfaces you experience. Even the smallest improvements really add up. Tribology may be a funny-sounding word, but it has a huge impact on our world.

我鼓励大家 关注身边的摩擦学， 并且考虑如何改善 自己遇到的相互作用面。 即使是最微小的改善， 也可能产生 积少成多的效果。 摩擦学也许听起来滑稽， 但它对我们的世界 有着很大的影响。

11:47

Thank you.

谢谢。

11:48

(Applause)

（掌声）