5results about How to "Uniform strain distribution" patented technology

The invention discloses a molded surface pre-dispersion superplastic forming / diffusion bonding method, and belongs to the field of superplastic forming. The method solves the problem that when an ultrathin hollow multilayer structure is formed through an existing superplastic forming / diffusion bonding method, the wall thickness is not uniform due to excessive deformation of a core plate. According to the method, the core plate is subjected to large plastic deformation through a pre-reverse expansion method, stress concentration in a material is released, then the protruding part is subjected to plastic deformation through forward expansion, the core plate is subjected to plastic deformation in the reverse expansion stage, stress is more evenly distributed in the forward expansion stage, and therefore the situation that in a local area, the stress concentration in the material is reduced is avoided. And particularly, the phenomena of excessive deformation and thinning of high-strain parts such as fillets and the like are avoided, so that the uniformity of the wall thickness is greatly improved. The method provided by the invention comprises the following steps: (1) pre-forming a core plate and welding isolation ribs; (2) panel forming; (3) combining the core plate and the panel; (4) carrying out reverse expansion on the core plate; and (5) superplastic forming of the core plate.

This invention discloses a highly sensitive piezoelectric vibration sensing chip and its fabrication method that achieves differential cascading through electrode layout. An insulating layer, a lower electrode layer, a piezoelectric material sensitive layer, an upper electrode layer, and a passivation layer are sequentially stacked on the upper silicon surface of an SOI silicon substrate. A fixed frame and a central mass block are fabricated on the SOI silicon substrate. The portions of the buried oxide layer, upper silicon layer, insulating layer, lower electrode layer, piezoelectric material sensitive layer, and upper electrode layer opposite to the annular cavity form annular diaphragms. Multiple sets of electrode units are arranged on the upper electrode layer at positions corresponding to the stress concentration areas of the annular diaphragms. Gaps exist between the first and second annular electrodes and at the strain-neutral interface of the annular diaphragm. Electrode leads are connected to the lower electrode layer and the first and second annular electrodes of each electrode unit. All electrode leads are electrically connected to the electrode units of the upper electrode layer and the lower electrode layer at different polarity terminals to achieve differential interconnection of the output charge.

The invention provides a forge piece design method for preventing a deformation dead zone at the bottom of a large barrel-shaped forge piece. The method comprises the steps that a two-step boss structure is additionally arranged on the outer side area of the flat bottom of the forge piece; performing shape matching design on a lower die or a lower ejection die structure corresponding to the bottom of the forge piece; carrying out three-dimensional modeling; performing analog simulation on the large special-shaped barrel forge piece, and adjusting the height and width of a two-step boss structure at the bottom of the forge piece and the matched shape and size of a lower die or a lower ejection die according to strain distribution of the large special-shaped barrel forge piece; streamline distribution of the large special-shaped barrel forge piece is analyzed, it is ensured that a to-be-machined part area is uniform in deformation and smooth in streamline, and the structure property requirement is met. According to the method, deformation dead zones on the two sides can be effectively moved outwards or downwards to the position below the to-be-machined part area, meanwhile, the possibility that the deformation dead zones appear in the center area is prevented due to increase of the bottom deformation amount, and it is greatly guaranteed that strain of the to-be-machined part area at the bottom of the large special-shaped barrel-shaped forge piece is evenly distributed, and the streamline is smooth and reasonable.

The utility model relates to a herringbone support steel frame. The method is suitable for the technical field of building structure engineering. According to the technical scheme, the steel frame comprises a steel frame body which comprises a steel beam, steel columns and steel supports, the steel columns are perpendicularly connected to the two ends of the steel beam, and the steel supports which are symmetrically arranged are obliquely connected between the middle bottom of the steel beam and the bottoms of the inner sides of the steel columns; a first joint close to the symmetric center line of the steel beam and a second joint far away from the symmetric center line of the steel beam are respectively formed between the two sides of the steel support and the bottom of the steel beam through the steel support flange plates; the inclined stiffening plate structures are arranged in the middle of the steel beam in an inclined mode, the arrangement positions of the inclined stiffening plate structures correspond to the first connecting positions, the inclined stiffening plate structures are symmetrically arranged about the symmetrical center line of the steel beam, and the included angle opening direction of the inclined stiffening plate structures is consistent with the included angle opening direction of the steel support; and the vertical stiffening plate structures are arranged in the middle of the steel beam and are vertically arranged, the arrangement positions correspond to the second connecting positions, and the vertical stiffening plate structures are symmetrically arranged about the symmetric center line of the steel beam.

This invention relates to a die design method for controlling the strain and filling of high-lumen forgings, belonging to the field of forging die design technology. The method includes: using full-process numerical simulation technology to simulate and analyze the forging process, determining the height and diameter of the blank (L1 and h1); designing the lower die and its cavity based on the forging contour (h2); designing the upper die and its deep cavity based on the high-lumen forging (H, α, R, and L2 < L1); obtaining the upper die's downward pressure t during forging, where t = h1 - h2; comparing the relationship between H and 0.68t to obtain the comparison result; and determining the values ​​of α and R based on the comparison result. This method controls the strain of the high-lumen forging during forging by adjusting the height of the blank, ensuring complete filling of the deep cavity.