| Cast aluminum alloy ZL105 has good casting process performance and is often used in the manufacture of engine cylinder heads and various casing parts.Carbon nanotubes have the advantages of high specific strength and low density,and are ideal reinforcements for metal matrix composites.In order to improve the casting quality and performance of cylinder head products,this paper explores the addition of carbon nanotubes to ZL105 alloy to enhance the mechanical properties of composites,and carry out research on the heat treatment process of materials,finally,the prepared carbon nanotube aluminum matrix composites were formed in 912 D series air-cooled diesel engine cylinder head products,and the effects of different materials on the performance of cylinder head products were compared.In this paper,carbon nanotubes with different contents and aspect ratios were added to ZL105 aluminum matrix by stirring melt casting method,and the effects of carbon nanotube reinforcement contents and aspect ratio on the mechanical properties of the alloy were analyzed.On the basis of this formula,the optimal heat treatment process of carbon nanotube reinforced cast aluminum alloy ZL105 composite material was obtained by orthogonal experiment method,and the prepared material was finally used in the actual casting of cylinder head products.The paper first modified the aluminum matrix composites by adding carbon nanotubes with different contents and aspect ratios.Studies have shown that adding carbon nanotubes will improve the tensile strength and hardness of composites,and when the mass fraction of carbon nanotubes is 1.25%,the maximum mechanical properties can be obtained.The strengthening mechanism of the composite material is the result of the joint effect of various strengthening methods,but to a certain extent,the hardness of the composite material will be weakened;Adding carbon nanotubes with relatively small aspect ratios can better improve the mechanical properties of the composites.Secondly,the heat treatment process was analyzed by the orthogonal experiment method.The results showed that the solution time had the greatest influence on the mechanical properties of the composites,followed by the aging time on the strength of the composites.The heat treatment parameters of solution temperature and aging temperature have a significant effect on the strength of composites,but have little effect on hardness and elongation.In addition,the reason why solution aging heat treatment enhances the mechanical properties of composites is the combined effect of solid solution strengthening,dispersion strengthening and precipitation strengthening in the composites.Finally,the prepared carbon nanotube-modified composite material is used to cast the cylinder head product.The results show that the mechanical properties of the prepared engine cylinder head product have been improved to a certain extent.Based on material research and the material used in the preparation of engine cylinder heads,this paper explores a new research path for new materials in the forming technology of auto parts.It effectively expands the application range of this type of composite material,and has practical significance for the application of new materials to form auto parts. |
