4results about How to "Small size shrinkage" patented technology

The application provides a high-performance titanium-based part powder hot isostatic pressing preparation method based on low-cost near-spherical bimodal powder. The preparation method uses a near-spherical bimodal particle size distribution titanium-based powder with good uniformity and high tap density as raw material, and combines powder hot isostatic pressing technology to prepare a high-performance low-cost titanium-based part, so as to meet the high-performance low-cost demand of complex structure and thin-walled titanium alloy parts in the fields of aerospace, weapon equipment and the like.

The application provides a bismaleimide-polyether amine photocuring resin and a preparation method thereof. 100 parts of bismaleimide and 100-200 parts of polyether amine are pre-reacted, 0.001-5 parts of a catalyst, 0.001-1 parts of a polymerization inhibitor and 100-400 parts of glycidyl methacrylate are added to carry out grafting reaction, and the bismaleimide-polyether amine photocuring resin is obtained. The bismaleimide-polyether amine photocuring resin provided by the application has the characteristics of realizing photocuring through ultraviolet light irradiation on the basis of retaining the excellent thermal performance and good mechanical performance of traditional bismaleimide, and effectively solves the problem of poor forming performance. The method disclosed by the application has simple process and mild reaction conditions, is suitable for industrial production, and the prepared material has wide application potential in the fields of photocuring printing and electronic packaging.

The application discloses a preparation method of an alumina aerogel heat insulation felt, and comprises the following steps: adding an aluminum source precursor into a ketone substance to form a precursor solution through sufficient dissolution; adding an alcohol solvent containing a silicon source precursor, an amine substance and a catalyst into the precursor solution to form an alumina sol through uniform stirring; adding a surfactant into the alumina sol to form an alumina sol containing a light shielding agent through uniform stirring; adding light shielding agent particles into the alumina sol to form the alumina sol containing the light shielding agent; immersing a ceramic fiber felt into the alumina sol containing the light shielding agent to perform gel aging, so as to obtain a fiber felt / gel composite; and performing drying and heat treatment on the fiber felt / gel composite, so as to obtain the alumina aerogel heat insulation felt. The alumina aerogel heat insulation felt prepared by the method has the advantages of high temperature resistance, excellent heat insulation performance and good flexibility.

This invention provides a direct-write printing method for preparing a three-dimensional porous polyimide-hollow glass microsphere composite material and the resulting material. The method includes: S1 preparing a soluble polyimide-hollow glass microsphere composite material; S2 preparing a direct-write printing composite ink; S3 direct-write printing and humidification pre-gelling; S4 solvent-inducing phase transition curing to create pores; and S5 low-temperature drying to obtain the finished product. This invention utilizes chemical bonding to construct an organic-inorganic cross-linked network, avoiding interfacial gaps and filler sedimentation. It eliminates the need for photosensitizers and high-temperature treatment, resulting in a simple process, high molding precision, and low shrinkage. The prepared composite material possesses a nanoscale three-dimensional interconnected porous structure with strong interfacial bonding, lightweight yet high strength, and excellent thermal insulation properties. It effectively solves the problems of easy collapse, uneven pore size, and complex processes in existing 3D printing of porous polyimide materials, making it suitable for applications such as thermal insulation, sound absorption, and catalyst support.