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Due to the large number of blind individuals and the shortage of donor corneas available for transplantation, artificial corneas have gradually become a research hotspot, However, artificial corneas often experience implant tearing due to insufficient mechanical properties. In order to solve this problem, researchers at home and abroad have tried to improve the mechanical properties of corneal repair materials by a series of research work. This paper summarizes the progress relating to the mechanical properties of four common natural polymer-based corneal repair materials, namely collagen, gelatin, silk fibroin, and chitosan. The results show that physical methods such as photo-crosslinking and thermal crosslinking, chemical methods such as 1(3-dimethylaminopropyl) -3-ethylcarbodiimide (EDC)/N-hydroxysuccinimide (NHS) crosslinking, genipine or glutaraldehyde crosslinking and other composite methods can significantly improve the mechanical properties of corneal materials, but these methods still have some shortcomings. Therefore, further development of high-quality artificial corneas is crucial. It is hoped that the article can provide some reference and ideas for the study of improving the mechanical properties of corneal repair materials through summarization. [ABSTRACT FROM AUTHOR]

Molten metal die forging (MMDF) processes is an advanced process for high-performance forming of aluminum alloy parts, MMDF technology is applied to the forming of closed subframes, fo- cusing on the performance uniformity of MMDF process scheme and MMDF subframe in this paper. Simulation studies show that single-runner MMDF has fewer confluence positions, higher surface quality and higher process yield than MMDF solutions with auxiliary runners. Trial production proves that the single runner liquid forging of A356. 2 aluminum alloy subframe can be obtained by using the HVSC2500T horizontal MMDF machine designed and manufactured by Guangzhou Hede, and the sampling tensile strength of the body can reach 320 MPa while the elongation is 11. 12%. However, slag inclusion defects are prevalent in locations away from the sprue and where there is a confluence, and the strength and plasticity are low. [ABSTRACT FROM AUTHOR]

So as to investigate the influence of intercritical annealing time on microstructure and mechanical properties of medium Mn steels based on the results of SEM, XRD and tensile properties, a Fe-0.21C-0.20Si-6.1Mn-0.97Al alloy was treated at different annealing times（10min,1hand 12h）in this papers. The results showed that the increase in annealing times from 10min to 1hled to the increase in mechanical properties of warm rolled medium Mn steels,as the annealing time further increased to 12h, the mechanical properties of the experimental steel decreased; the increase in annealing time led to the increase in average grain size and the equiaxed microstructure ratio; with the increase of annealing time from 10min to 12h, the retained austenite fraction and stability increased firstly, and then decreased. Based on the above results, it can be inferred that the microstructure and mechanical properties of medium Mn steel could be controlled by controlling the annealing time. [ABSTRACT FROM AUTHOR]