Beveled two-stage anvil for enhanced high-pressure sealing and operational efficiency

The two-stage large-volume press system, achieved by adding eight truncated cube anvils in the primary pressure chamber, can extend the routine cell pressure range to above 10 GPa. However, this system necessitates a critical trade-off between experimental duration and sealing reliability: extended compression and decompression times are typically required to avoid seal failure (blow-out). In this work, we introduce the trapezoidal beveled two-stage anvil, which can markedly improve both pressure sealing performance and operational efficiency. The optimized anvil design effectively prevents blow-out during rapid decompression-reducing the failure rate from ∼90% to nearly zero under 30-min decompression-while cutting the experimental cycle time by more than 50%. This development holds the promise to resolve the critical trade-off between experimental duration and sealing reliability for the two-stage large-volume high-pressure system.