Reliability analysis of the global graphite trade industry chain risk assessment based on percolation theory

Graphite, as a critical strategic mineral resource, holds a significant position in the global high-tech industry, and its reliability is essential for global economic stability. To address the resilience and stability of the graphite trade network, we propose a method based on an improved Pointwise Mutual Information (PMI) and percolation theory. By constructing a directed weighted network reflecting trade dependencies between countries, we evaluate the network’s performance under different risk scenarios. The model employs PMI to quantify trade dependencies and uses percolation theory to simulate both random and targeted disruptions, analyzing the network integrity of various stages of the graphite supply chain in the context of edge removals. Key metrics include the Largest Weakly Connected Component (LWCC) and Critical Link Scores (CLSs), which are used to assess structural robustness and identify critical trade links. The results indicate that network structure and connectivity density are key determinants of its resilience. The upstream network stage is relatively vulnerable due to its dependence on high-weight connections, whereas the midstream and downstream stages exhibit higher resilience due to diversification in trade relationships. Enhancing the maximum critical links is crucial for improving network reliability. This study innovatively proposes a systematic risk mapping and mitigation approach for strategic material networks, providing practical recommendations for international trade policy and supply chain optimization. Additionally, policy recommendations focusing on countries with high CLSs are particularly important, as they can help nations formulate effective response strategies.