Pressing forward with high-pressure generation

Deep within the Earth, kilometers of rock apply immense temperatures and pressures on atoms, squishing them into new formations with new properties. Reproducing such processes in the real world is no easy feat: To simulate similar pressures, researchers need a machine that can transmit extraordinarily targeted force.

Niu et al. systematically optimized the gasket geometry, anvil hardness, and anvil taper of a multi-anvil press to raise the machine’s achievable pressure to 45 gigapascals for a 10 mm³-volume sample. The pressure far surpassed the longstanding 25 gigapascal limit for such instruments.

Regarding high-pressure instrumentation, “There is a long-pursued trade-off,” said author Guoliang Niu. “When you want to generate a higher pressure, you usually will lose the volume of the sample.”

But reducing sample volumes, which are already at millimeter scales, is often not industrially useful. So, to achieve high pressures without requiring smaller samples, previous researchers began by reducing the taper angle of the tungsten carbide anvils by one degree each. Seeing limited success, Niu et al. chose to reduce the volume of the instrument’s gasket seal, which often subsumes force instead of passing it along to the sample. They also used harder tungsten carbide anvils. The changes resulted in an 80% pressure boost.

The researchers hope their findings can be applied to geoscience and materials science laboratories globally, enabling them to synthesize materials at pressures similar to Earth’s lower mantle. Next, they hope to develop thermal insulation for their multi-anvil press, since many high-pressure experiments also require high temperatures.

Source: “High-pressure generation above 45 GPa over a 10 mm³ volume with a multi-anvil press,” by Guoliang Niu, Lianjie Man, Peiyang Mu, Junkai Li, Rémy Pierru, Amrita Chakraborti, Shuai Tang, Cheng Qian, Shengbo Cao, Shijing Zhao, Bingmin Yan, Robert Farla, Chunyin Zhou, Xiaokang Feng, Youwen Long, Ke Yang, Kui Han, and Huiyang Gou, Review of Scientific Instruments (2026). The article can be accessed at https://doi.org/10.1063/5.0323039 .