The Birth of 'Unbreakable Glass'

A short video that went viral online recently shows the screen of a Huawei smartphone remaining intact after being used to crack walnuts, hammer nails, and driven over by a car.

This remarkable strength and durability is attributed to the phone's nanocrystalline glass, or Kunlun Glass, a completely homemade product by a local enterprise called Chongqing Aureavia Hi-tech Glass Co., Ltd. (ATG), which has spent years perfecting the technology.

From lab to factory

So, how can a small piece of glass that is only about half a millimeter thick be so tough?

"That's because a palm-size piece of microcrystalline glass is filled with billions of high-strength nanocrystals," Jiang Hong, a renowned expert in the field of specialized glass in China, told Science and Technology Daily. "The regular arrangement of these crystals endows the material with superior physical and chemical properties, which can effectively block cracks and greatly improve the strength and resistance of the glass."

Therefore, specialized glass, including the nanocrystal glass line, has a huge demand in many other emerging industries, apart from smartphones.

However, this market has long been monopolized by foreign manufacturers. Learning about this situation, Bai Yibo, an entrepreneur in Chongqing conceived the idea of stepping into the field of new materials. At the same time, Jiang's research results in aviation glass and mobile phone screens were urgently in need of industrialization. Sharing the same vision, the two visionaries joined hands and established ATG in July 2014.

Although ATG holds Jiang's pioneering technology, Bai soon realized that the industrial mass production was far more difficult than expected.

Removing the bubbles

From the construction of ATG in 2014 to the launch of the production line in 2018, an investment of up to 400 million RMB was pumped into the company. But the mass production faced a major challenge as the output was always plagued with defective glass filled with bubbles.

"The theoretic formula can be verified in the laboratory, but the production process can only be adjusted and demonstrated on the production line," said Peng Can, head of the equipment power department of ATG, who has rich experience in glass production and factory construction.

After in-depth analysis, the engineers found that bubbles are generated when the glass liquid comes into contact with the bottom of the kiln. To reduce bubbles, it is necessary to cool the kiln. But the cooling effect of conventional air blowing is limited. To solve the problem, some young technicians have put forward a bold idea to throw a "water bag" into the kiln.

After careful calculation, the technicians introduced a "water bag" made of steel plates (similar to an iron water pipe) into the kiln by 10 millimeters every two hours to cool the wall, while finely adjusting various parameters. Half a month later, the bubbles in the glass finally disappeared.

This technological innovation has increased the qualification rate of glass to 80 percent, paving the way for large-scale production. With continuous improvement of the process, the qualification rate has gradually increased to 97 percent.

More benefits

In 2021, China's first nanocrystal glass line was finally produced. Jiang said that the key to success lies in ATG's technology to integrate a large number of nano microcrystals into the glass. The core of the technology is the precise control of temperature by their self-developed equipment called a tunnel kiln.

After ten years, ATG's dedication to innovation has finally shattered international barriers. Its nanocrystalline glass obtained the Swiss SGS five-star glass drop resistance certification, a testament to its resilience against impact.

Currently, the company has applied for more than 350 patents at home and abroad, including 282 invention patents. The products are widely used in fields such as smart home appliances, aviation, high-speed rail and new energy vehicles, providing strong support for the development of China's high-end manufacturing industry.

In the future, Bai envisions constructing an electronic cover glass industrial cluster. He predicts that by 2025, the company can generate sales revenue of more than two billion RMB, which can drive upstream and downstream enterprises in the industrial chain to create tens of thousands of jobs.

As China has emphasized the development of new quality productive forces, the company will remain committed to innovation of original and cutting-edge technologies, contributing to industrial modernization, and fostering advancements that benefit both the nation and the world, said Bai.

Source: Science and Technology Daily