Preparation method for precision-investment casting mold shell of easily-oxidized metals
What is Al technical title?
Al technical title is built by PatSnap Al team. It summarizes the technical point description of the patent document.
A technology of investment precision casting and easily oxidized metals, which is applied in casting molding equipment, metal processing equipment, casting molds, etc., and can solve problems such as poor stability of yttrium sol binder, expensive yttrium oxide material, and long drying time of mold shells , to achieve the effect of improving close packing ability, reducing shell manufacturing cost and low price
Active Publication Date: 2017-09-15
SHENYANG RES INST OF FOUNDRY
View PDF5 Cites 7 Cited by
Summary
Abstract
Description
Claims
Application Information
AI Technical Summary
This helps you quickly interpret patents by identifying the three key elements:
Problems solved by technology
Method used
Benefits of technology
Problems solved by technology
However, there are certain problems in this process technology. On the one hand, the yttrium oxide material is relatively expensive, resulting in high production costs. On the other hand, the yttrium sol binder has poor stability during the preparation process and is prone to gelation. Zirconium acetate binder The gelling speed is slow and reversible during the shell making process. After gelling, it will "dissolve" when it encounters water, and it will fall off from the wax mold. Therefore, the shell needs a long drying time, resulting in a mold preparation cycle. longer
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0018] An investment casting method for easily oxidized metals, taking the titanium alloy pump body whose material grade is ZTA15 as an example, the process steps are as follows:
[0019] (1) Form shell surface layer preparation: add refractory powder into the binder and mix well, the mass ratio of powder to liquid is 3:1, and add 0.02wt% wetting agent JFC and 0.02wt% defoamer n-butanol , stirred evenly for 6 hours, and prepared into a surface coating; wherein the composition of the refractory powder is 80% calcium zirconate, 20% yttrium oxide, the particle size is 270-650 mesh, and the composition of the binder is 50% nano-alumina dispersion , 50% zirconium acetate, the concentration of nano-alumina dispersion liquid is 20wt%, and the concentration of zirconium acetate is 40wt%. The coating is hung on the wax model, sanding adopts calcium zirconate sand, the particle size is controlled at 80 mesh, the drying time is controlled at 12 hours, the ambient temperature is controlle...
Embodiment 2
[0025] An investment casting method for easily oxidized metals, taking the production of a zirconium alloy plug valve whose material grade is 702C as an example, the process steps are as follows:
[0026] (1) Form shell surface layer preparation: add refractory powder into the binder and mix well, the mass ratio of powder to liquid is 2:1, and add 0.02wt% wetting agent JFC and 0.02wt% defoamer n-butanol , stirred evenly for 6 hours, and prepared into a surface coating; wherein the composition of the refractory powder is 60% of calcium zirconate, 40% of yttrium oxide, the particle size is 270-650 mesh, and the composition of the binder is 60% of nano-alumina dispersion , zirconium acetate 40%; the concentration of the nano-alumina dispersion liquid is 20wt%, and the concentration of zirconium acetate is 40wt%. The coating is hung on the wax model, and the sand is sprinkled with calcium zirconate sand, the particle size is 80 mesh, the drying time is 12 hours, the ambient temper...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more
PUM
Property
Measurement
Unit
particle size
aaaaa
aaaaa
surface roughness
aaaaa
aaaaa
Login to view more
Abstract
The invention provides a precision-investment casting method for easily-oxidized metals. The precision-investment casting method comprises the following steps of (1) preparation of a surface layer of a mold shell, specifically, a refractory powder is added into a binder and evenly mixed, a wetting agent and an antiforming agent are further added, and even mixing is conducted to prepare surface layer coating; and the coating is smeared on a wax patter, and after drying, the above operations are repeated for many times to form a surface layer mold shell; (2) preparation of a reinforcement layer of the mold shell, specifically, a bauxite powder is added into a silica sol binder and evenly mixed, bauxite sand is adopted to conduct stuccoing, and after drying, the above operations are repeated for many times to form a reinforcement layer mold shell; (3) mold shell dewaxing and roasting, specifically, an infrared dewaxing technology is adopted; and (4) melting and pouring, a vacuum consumable kish melting method is adopted to conduct melting, and a centrifugal pouring technology is adopted to conduct pouring. According to the precision-investment casting method for easily-oxidized metals, a casting produced by adopting the method is precise in size, the minimum wall thickness is small than or equal to 1.0 mm, the surface roughness is smaller than or equal to 6.3 mu m, the surface reaction layer is smaller than or equal to 0.03 mm, and the surface is free of the defects of cold shut, flow marks, microcracks and the like; and moreover the production cost is reduced, the production cycle is shortened, and the method is suitable for volume production.
Description
technical field [0001] The invention relates to a process method for preparing investment casting mold shells for easily oxidized metals. Background technique [0002] Easily oxidizable metals (titanium, zirconium, etc.) have the characteristics of low density, high specific strength, and corrosion resistance, and have been widely used in aviation, aerospace, nuclear energy, chemical, and medical industries. Easily oxidizable metals have high activity in the molten state, and can chemically react with commonly used refractory materials to varying degrees, and can also react with O 2 , N 2 、H 2 and CO 2 And other gases have chemical reactions, affecting the quality of castings. Therefore, the casting technology of easily oxidized metals has high requirements on casting materials and casting equipment, and appropriate casting materials and casting methods must be selected to ensure the quality of castings. [0003] At present, the oxidizable metal casting technology mainl...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more
Application Information
Patent Timeline
Application Date:The date an application was filed.
Publication Date:The date a patent or application was officially published.
First Publication Date:The earliest publication date of a patent with the same application number.
Issue Date:Publication date of the patent grant document.
PCT Entry Date:The Entry date of PCT National Phase.
Estimated Expiry Date:The statutory expiry date of a patent right according to the Patent Law, and it is the longest term of protection that the patent right can achieve without the termination of the patent right due to other reasons(Term extension factor has been taken into account ).
Invalid Date:Actual expiry date is based on effective date or publication date of legal transaction data of invalid patent.
Login to view more