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In order to meet the demand for high wear-resistant Co-based material used in fields such as aerospace, energy, medical, etc., this study attempts to improve the comprehensive performance of this material by adding some reinforced phases and adjusting the sintering temperature. Results indicate the pure Co–Cr–W alloy is composed of γ-Co, M29C, and M6C (Ni3W3C), and the Co–Cr–W matrix composites are composed of γ-Co, M29C, M6C (Co2W4C), M23C6, and WC. With increasing the hot-pressing sintering temperature, the element diffusion in the material becomes sufficient, and the microstructure of Co–Cr–W alloy and composites materials becomes denser. When the sintering temperature is over 1150 °C, the bending strength and the toughness of the Co–Cr–W matrix composites are higher than that of the pure Co–Cr–W alloys. The added reinforced phases help the composites to gain a multi-scale strengthening effect, which makes the composites have a more comprehensive performance. Our results emphasize the importance of added reinforced phases and help to optimize the preparing process in preparing the Co–Cr–W alloys.

Porcine epidemic diarrhea (PED) is a highly contagious disease in newborn piglets. In our previous study, a genetically engineered Lactobacillus casei oral vaccine (pPG-COE-DCpep/L393) expressing a dendritic cell (DC)-targeting peptide fused with porcine epidemic diarrhea virus (PEDV) COE antigen was developed. This vaccine induced significant levels of anti-PEDV specific IgG and IgA antibody responses in mice, indicating a potential strategy against PEDV infection. In this study, pPG-COE-DCpep/L393 was used for oral vaccination of newborn piglets against PEDV. We then assessed the immune responses and protection efficacy of pPG-COE-DCpep/L393. An indirect enzyme-linked immunosorbent assay (ELISA) showed that the recombinant Lactobacillus vaccine elicits a specific systemic and mucosal immune response. The T-helper cells mediated by pPG-COE-DCpep/L393 and PEDV infection display a Th1 phenotype. The histopathological results showed that pPG-COE-DCpep/L393 promotes lymphocyte proliferation and effectively protects piglets against PEDV infection. The transforming growth factor-β level indicated that the recombinant Lactobacillus vaccine plays a role in anti-inflammatory responses in mesenteric lymph nodes during PEDV infection. These results show that pPG-COE-DCpep/L393 is a potential vaccine against PEDV infection.