【经济学人】3D打印运用到军事啦 | 2016.11.05 | 总第721期

• Spare：n.备用零部件

Having access to a printer can even encourage innovation. For example, the USS Harry S. Truman, an American aircraft-carrier , took two 3D printers on her most recent tour of duty in the eastern Mediterranean and the Persian  Gulf, which began in November 2015. During the eight months she was at sea her crew devised and printed such items as better funnels for oil cans (to reduce spillage), protective covers for light switches (to stop people bumping into them and inadvertently plunging, say, the flight deck into darkness) and also a cleverly shaped widget they dubbed the TruClip. This snaps onto walkie-talkies , reinforcing a connection that is otherwise prone to break in the rough-and-tumble of naval usage. According to Commander Al Palmer, one of the Truman’s maintenance officers, TruClips alone have saved more than $40,000 in replacement parts. The printers themselves, by contrast, cost about $2,000 each. On the basis of his experience using it, Commander Palmer reckons 3D printing will become an important part of the American navy’s supply chains.

3D打印的使用有助于激励创新。例如，美国的Harry S. Truman号航空母舰，就曾在最近的东地中海和波斯湾巡航中（从2015年9月开始）携带两台3D打印机。在八个月航期里，船员们设计并打印了一种更方便的油罐漏斗（用以减少漏油）、一种带有防护盖的电灯开关（防止船员不小心碰到开关，关掉飞行甲板上的跑到显示灯）还有名为TruClip的巧妙的小装置。将其装在对讲机上可以增强信号，防止恶劣的航海条件下的信号中断。军舰上维修部门的指挥官Al Palmer说，单TruClips的设计就在部件更换方面节约了40000美元。相比之下，这些打印机每个只需2000美元。基于3D打印机的使用经验，Palmer认为，3D打印技术将会成为美国航海装备供应链的重要组成部分。

• Aircraft-carrier： 航空母舰

• Funnel：漏斗

• Walkie-talkies：手提无线电话机

Keep your powder dry

固定金属粉

At the moment, only plastic items can be printed at sea. Landlubbing printers can make things out of metal by building up layers of metallic powder that are then melted with a laser or electron beam and allowed to cool into a solid. But printers, like people, get seasick. A ship’s constant yawing, pitching and rolling disturbs the powder before the beam can do its work. This is why a printer of metal ship parts operated by Canada’s navy sits safely on dry land, at the Cape Scott fleet-maintenance facility in Halifax, Nova   Scotia.

目前,海上只能打印塑料物品。而陆地上的打印机可以打印金属物品。陆地打印机通过层层地堆积金属粉末，然后用激光或电子束将其融化随后冷成型。但是打印机跟人一样，也会晕船。由于船不停地晃动、冲撞和起伏，导致金属粉末在融化前就已被冲散。这就是为什么加拿大海军基地把其船体金属部件打印机设在安全的陆地上的原因（Scott海角战舰维修点位于新斯科舍的哈利法克斯城）。

• Layer of metallic powder：金属粉末层

• 注：哈利法克斯在法律上称为哈利法克斯区域自治市（人力资源管理），是新斯科舍省省会加拿大的首府。