The titanium rivets on the aircraft carrier are so expensive: one can change for an Audi

The cost of a rivet is at least 100,000 yuan, and not every country has the ability to process it. If you rely on import prices will be higher. The rivet is made of titanium alloy. Titanium is considered a rare metal. This is due to its presence in nature and its difficulty in extraction. It is characterized by light weight, high strength, metallic luster, and good corrosion resistance (including seawater, aqua regia and chlorine gas). Because of its stable chemical properties, good high temperature resistance, low temperature resistance, strong acid resistance, strong alkali resistance, and high strength and low density, it is known as "space metal".

In fact, not all rivets on the aircraft carrier are valuable, and one is worth RMB 10,000 in my country. But titanium rivets abroad are valuable, and Audi is much cheaper. But there are also rivets that are worth an Audi. These expensive rivets are used on aircraft carriers with vertical take-off and landing functions, because these rivets have to withstand flames of up to 1000 degrees when they take off from vertical take-off and landing fighters.

Titanium rivets are really expensive in processing technology. The market price of titanium gold is US$28/kg, which is about 90 yuan per kilogram. The recycling price of titanium alloy scrap is about 50 yuan per kilogram.

The reason why titanium alloy products are so expensive is not that their materials are valuable. The most expensive titanium alloy sold in the metal materials market will not exceed 600 yuan per kilogram. The reason why titanium alloy products are so expensive is that their processing costs are high. Titanium alloy materials are recognized as one of the most difficult materials in the machining industry. Its processing cost is several to tens of times of its material value. To give you a brief description of a characteristic of titanium alloy, you can see the difficulty of processing. "Low thermal conductivity" means that the heat transfer is slow. If the heat transfer is slow, the heat will locally accumulate during machining and it is easy to burn out the tool. Therefore, in order not to generate a lot of heat, the cutting speed of the tool when processing titanium alloy is very slow, so the processing time is very long. In order to improve the processing efficiency of titanium alloys, some large factories use liquid nitrogen for processing cooling. In addition, the fine particles of titanium alloy chips cut off during processing will burn at a temperature of about 200 degrees when the cooling is not good. Machining the work pieces that risked a fire hazard is naturally expensive.