Kedong Zhang

Residual thermal stresses from Physical Vapor Deposition (PVD) trigger premature delamination in DLC/TiAlN coatings by weakening interfacial adhesion. To improve coating reliability, this study establishes a thermo-mechanically coupled finite element framework to quantify how deposition temperature and film thickness dictate stress evolution. Simulation results demonstrate that a 150 °C deposition temperature and a 3 μm TiAlN interlayer synergistically reduce interfacial shear stress by 42%. Experimental validation confirms an optimized wear depth of 2.9 ± 0.3 μm and a 68% increase in critical load (Lc). The optimized architecture triggers a transition from brittle fracture to ductile-dominated failure, providing a quantitative “low-stress, high-toughness” design paradigm for DLC-based composite coatings.

Primary breast signet ring cell carcinoma (BSRCC) is an extremely rare malignancy with poor prognosis. Few consensus exists regarding the prognostic factors and treatment modalities. This study aimed to develop a nomogram model to predict survival probability and guide clinical treatment for BSRCC patients. Clinicopathological data of BSRCC patients were retrieved from SEER database. Univariate and multivariate Cox regression analyses were performed to screen and identify prognostic factors. Kaplan–Meier method was used to describe the survival curve for each prognostic factor. Additionally, these factors were incorporated to construct nomograms for predicting overall survival (OS) and disease-specific survival (DSS) of BSRCC patients. The nomograms were internally validated using receiver operating characteristic (ROC) curves, calibration curves and decision curve analysis (DCA). A total of 362 eligible BSRCC patients were included in this study. Multivariate Cox analysis demonstrated that age at diagnosis, T stage, N stage, and surgery were identified as independent prognostic factors for OS, while grade, T stage, N stage, ER status, and surgery were independent DSS-related factors. Our study elucidated that surgery is the effective treatment for BSRCC, while postoperative radiotherapy does not confer additional benefit to patients. Nomograms were established to predict OS and DSS probability by incorporating independent prognostic factors among BSRCC patients. The nomograms were subsequently validated using ROC curves, calibration curves, and DCA to display the robust prognostic capability. Robust nomograms for OS and DSS of BSRCC patients were established, facilitating precise personalized risk assessment and appropriate treatment regimens in clinical practice.

ZrO₂ ceramics, known for their high strength and wear resistance, are ideal for artificial joints. This study enhanced the friction performance of these joints by fabricating textured structures (50 μm width and 20–25 μm depth) on the ceramic surface. Friction tests, conducted at 200 r/min for 30 min with a 5–20 N load and lubricant concentration of 15–60 mg/mL using PEEK balls, showed that textured joints outperformed untextured ones. The symmetrical triangular structure had the lowest coefficient of friction and the best hydrophilicity, with a 53.0% reduction in the coefficient of friction and a 57.4% reduction in the contact angle compared to the untextured structure. The textures effectively store the PEEK residue and facilitate the smooth movement of the worn ball. Concurrently, the textured structure stores some of the lubricant, which reduces the static pressure during fluid flow by 12.6%. Overall, the friction performance of ZrO₂ ceramic artificial joints was significantly improved by the textured structures.