30results about How to "Increase damage tolerance" patented technology

An extruded structural member having improved damage tolerance containing a base section (6); a stiffening section having at least one pair of structural stiffeners (10), the structural stiffeners integral with the base section (6) and projecting outwardly thereof; and at least one intra-stiffener (90) area positioned between the pair of structural stiffeners (10), the intra-stiffener area (90) having a microstructure with intentionally increased amounts of fiber texture to reduce the rate of fatigue crack growth in the extruded structural member.

The invention relates to a preparation method of a zirconium boride-based ultra-high temperature monolithic material, in particular to a preparation method of an in-plane isotropic zirconium boride-based ultra-high temperature monolithic structure ceramic with high damage tolerance, and aims to solve the problems that ZrB2-based ultra-high temperature ceramic has poor damage tolerance and seriousin-plane anisotropy exists in ZrB2-based fiber monolithic ceramic. The preparation method includes: dissolving polyether sulfone in N-methylpyrrolidone, and conducting ball milling mixing with ZrB2 powder and SiC powder to obtain a ZrB2-SiC slurry, and subjecting the ZrB2-SiC slurry to extrusion curing to obtain continuous ZrB2-SiC ceramic fiber; dispersing ZrB2 powder, SiC powder and Graphene indeionized water to obtain a ZrB2-SiC-Graphene slurry; coating the continuous ZrB2-SiC ceramic fiber with the ZrB2-SiC-Graphene slurry, performing drying, and conducting prepressing, high temperature glue discharge and hot pressing sintering. The method provided by the invention solves the in-plane anisotropy problem of uniaxially arranged ZrB2-based fiber monolithic ceramic, and improves the damage tolerance. The method provided by the invention is suitable for preparation of zirconium boride-based ultra-high temperature monolithic structure ceramic.

The invention belongs to the field of composite material preparation, and relates to a preparation method of a silicon carbide fiber reinforced silicon carbide ceramic matrix composite material. The method utilizes an automatic numerical control sewing system to realize automatic sewing of a two-dimensional SiC fiber preform, and adopts a precursor infiltration pyrolysis (PIP) process to prepare atwo-dimensional SiC/SiC composite material. By accurately controlling the tension of the suture lines, the laminated SiC fiber woven fabric is successfully sewn by using the SiC fibers. Compared witha conventional manual sewing method, the method can remarkably improve the sewing efficiency, quality and stability of the two-dimensional laminated SiC fiber woven fabric, and greatly reduces the preparation period and cost of the prefabricated body; meanwhile, SiC fibers are introduced between layers of the composite material, so the layering risk in the technological process can be reduced, and the interlayer mechanical property of the two-dimensional SiC/SiC composite material is effectively improved.

The invention discloses a steel reinforced concrete column-steel beam joint locally adopting fiber reinforced concrete. The steel reinforced concrete column-steel beam joint comprises core profile steel, the fiber reinforced concrete, a first steel beam, a second steel beam, a third steel beam and a fourth steel beam; the core profile steel comprises a first profile steel web and a second profilesteel web which are welded to form cross-shaped profile steel, the two ends of the first profile steel web are correspondingly provided with a first profile steel flange and a second profile steel flange, and the two ends of the second profile steel web are correspondingly provided with a third profile steel flange and a fourth profile steel flange; and the first profile steel flange, the second profile steel flange, the third profile steel flange and the fourth profile steel flange are correspondingly connected with the first steel beam, the second steel beam, the third steel beam and the fourth steel beam. The steel reinforced concrete column-steel beam joint locally adopting the fiber reinforced concrete has the characteristics that the fiber reinforced concrete is adopted at a joint core zone, the using amount of stirrups in the core zone can be reduced or even eliminated, the shear resistance capacity of the joint, the rotating capability of the joint and the energy dissipation capability can be remarkably improved, and meanwhile, construction complexity is reduced.

A method is presented for making a composite material from strips comprising longitudinal fibres and a binder or resin, which material comprises a number of layer assemblies one on top of the other. Each layer assembly comprises m sets (with m at least 2) of parallel strips each extending in a different direction, Each layer assembly is manufactured by successive steps of depositing groups of parallel strips according to a well defined pattern (without longitudinally interweaving strips with previously deposited strips). Before completing a layer assembly, with the exception of the last layer assembly, by depositing its last group of parallel strips, the first group of parallel strips of the following layer assembly is already deposited. A composite material manufactured with such a method is presented too.

Precast structures are formed of precast walls fitted between precast posts extending from cast in place footings, prior to the pouring of a slab. During pouring of the slab, anchors may tie together the panels, posts and slab. Precast concrete, tension fabric or traditional roofing members may be added to form a post and beam construction that spans large open areas providing for flexible manufacturing, storage, hangar, office, schools, institutional, or residential interior design features, due to the structural integrity and cost advantages of structures produced using this method of precast construction.

The invention discloses a multi-level micro-nano mechanical structure for enhancing damage resistance of a functional surface. The multi-level micro-nano mechanical structure comprises a micro-nano composite structure functional layer, an interconnection network structure functional layer and a mechanical artificial structure functional layer which are connected; the micro-nano composite structure functional layer is of a micro-column array structure which plays a surface function, the interconnection network structure functional layer is of a hard phase and soft interconnection structure, the hard phases are connected through soft phase materials to form an unstable parallelogram, and under the action of plane stress at the tail ends of micro-columns, spontaneous rotation or reconstruction is achieved, and apparent numerical values of stress and strain at the tail ends of the micro-columns are reduced; the mechanical artificial structure functional layer is of an array structure composed of reconfigurable artificial lattices with mechanical properties, and through time-space domain reconstruction of the artificial lattices, a stress transfer path and strain energy density are optimized, and stress concentration of a functional surface is reduced. According to the invention, a dynamic structure is introduced, the damage tolerance of the surface functional layer is improved, the service cycle of the functional surface is prolonged, and the performance of the functional surface is guaranteed.

The invention provides a thermoplastic wave-absorbing material and a preparation method thereof. The thermoplastic wave-absorbing material comprises: a reinforced fiber cloth; and thermoplastic wave-absorbing films positioned on the upper and lower side surfaces of the reinforced fiber cloth. According to the thermoplastic wave-absorbing material disclosed by the invention, the thermoplastic resin with a linear molecular structure is used as an adhesive matrix material, so that the thermoplastic wave-absorbing material has good toughness, the impact resistance and the damage tolerance of the thermoplastic wave-absorbing material can be greatly improved, and the thermoplastic wave-absorbing material can be processed and formed for multiple times and can be recycled, thereby being beneficial to environment protection and resource saving; and compared with the existing thermosetting wave-absorbing material, the thermoplastic wave-absorbing material disclosed by the invention only needs to be stored at normal temperature, and the storage period is not limited.

The invention relates to a method for producing, planar, simple or doubly folded core composites (1, 23) with at least one folded honeycomb core (4, 19). A hardening and later removable core filler (15, 16) is introduced into the through drainage channels (5, 6) of the folded honeycomb core (4, 19) before application of the initially unhardened surface layers (2, 3, 13, 22) in order to prevent a penetration of the cover layers, (2, 3, 13, 22) into the channels (5, 6) of the folded honeycomb core on the application and/or hardening of the surface layers (2, 3, 13, 22) and to achieve surfaces of the core composite (1, 23) without edges or polygons.