The difficulty in reducing car weight lies in the manufacturer's facilities

In recent years, automakers have made significant progress in improving fuel economy, but the essence of this is mainly around upgrading the efficiency of the powertrain. Compared with the early 1980s, today's cars are even slightly heavier. This is because in the more than a decade before the 1980s, the global automobile market had a strong demand for fuel economy.

At that time, cars began to reduce weight gradually in order to passively compensate for the lack of fuel-saving technology. However, modern people's concerns about safety have led manufacturers to improve the manufacturing quality and noise suppression capabilities of cars. At the same time, consumers' preference for large models has led to the weight of ordinary family vehicles remaining around two tons.

If automakers could slim down their models without sacrificing structural strength, safety, or comfort, they would have achieved greater results in improving fuel efficiency.

However, few consumers want to go back to driving noisy, fragile cars, so weight reduction can only be achieved at the molecular level. In a new study, the Center for Automotive Research, based in Ann Arbor, Michigan, surveyed the materials of 44 2015 models and asked automakers a question: If they had to reduce the weight of a major vehicle component in the short term, how would they respond?

With the help of nine automakers, the researchers conducted a detailed investigation of the components of different mass-produced vehicles. Although the above automakers provided detailed information on the components and assembly of the vehicles, the Center for Automotive Research was not allowed to disclose the specific models involved in the study. The researchers only said that the models they chose are very common on the road and their sales account for more than half of the total car sales in the United States.

"If you really want to reduce the weight of the car, you have to switch to composite materials on a large scale, especially carbon fiber," said Jay Baron, the leader of the research team, "even the vehicle's pillars, beams, longitudinal beams and other parts."

Baron said the message he's getting from automakers is that "it's hard to get more than 15% weight off a vehicle without relying heavily on composites."

Safety regulations from the National Highway Traffic Safety Administration and looser corporate average fuel economy standards are considered important factors in the lack of large-scale weight reduction in vehicles in recent years, but this move is imperative.

Under the country's latest fuel economy regulations, fuel mileage must be increased to 54.5 miles per gallon by 2025, so automakers have to seek help from body weight reduction.

However, the most common way to reduce weight is often by using high-temperature resistant plastics and reducing the size of the engine to reduce the weight of the latter itself.

The above study shows that when most automakers need to reduce 5% of the weight of a car, they usually turn to steel-aluminum integrated structure. Ford has used an all-aluminum body on the current F-150 model and further reduced weight by introducing modified plastics in other parts. However, the weakness of aluminum in durability limits its popularity.

Magnesium can also be used in conjunction with existing steel structure production facilities, but 67% of the metal's production is concentrated in China. Potential raw material supply issues make it less feasible for the metal to be used on a large scale among automakers in other countries. In addition, this move will significantly increase the latter's costs.

Carbon fiber and similar composite materials have the greatest value in terms of weight reduction, but almost all automakers agree that such materials are the most difficult to use in large-scale production. Using composite materials as the main material for automobile manufacturing may force automakers to abandon their existing production methods, but modular production is becoming more and more accepted in the industry. Once a major adjustment occurs, the cost will be unimaginably high.

Automakers generally agree that the biggest obstacle to reducing vehicle weight is the huge amount of money that has been invested in changing vehicle manufacturing standards. Based on this consideration, the trend in the next 10 years may be that automakers will introduce lighter materials in key areas such as doors, hoods, front pillars and surrounds, but their core materials will still be dominated by steel.

“Car manufacturers say to me, ‘We’ve worked so hard to come up with a standardized production process, and now you want us to make doors out of composites? That’s not standard, so you’re disrupting the process,’ ” Barron laughs.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.