阅读说明：本技术 一种高精度高质量的刀剪生产用粉末注射制造方法 (Powder injection manufacturing method for high-precision and high-quality knife and scissors production ) 是由 谢月光 莫仕栋 何冰强 吴远谋 吴棒记 于 2021-08-11 设计创作，主要内容包括：本发明公开了一种高精度高质量的刀剪生产用粉末注射制造方法,S1、材料混炼造粒：首先将合金粉末与粘结剂投入密炼机内进行均匀混合搅拌密炼,再将密炼完成后的混合材料投入造粒机中制粒,接着将制成的喂料收集并进行存储,本发明涉及粉末冶金技术领域；该高精度高质量的刀剪生产用粉末注射制造方法,通过在酸性气氛中催化脱脂去除大部分粘结剂,坯件保型性好,经后续高温烧结后成品组织的均匀性高、致密度好,物理性能可靠,精度高,同时明显降低了成品整体的加工成本,整体制程得到了缩短,实现了成品精度比铸造高,表面处理成本低,材料选择性高的效果,人员与设备也得到了大幅度的压缩。(The invention discloses a powder injection manufacturing method for high-precision and high-quality knife and shear production, which comprises the following steps of S1: firstly, alloy powder and a binder are put into an internal mixer for uniform mixing, stirring and internal mixing, then the mixed material after internal mixing is put into a granulator for granulation, and then the prepared feed is collected and stored, and the invention relates to the technical field of powder metallurgy; according to the powder injection manufacturing method for the high-precision and high-quality knife shear production, most of the binder is removed through catalytic degreasing in an acid atmosphere, the blank shape retention is good, the uniformity of the finished product structure after subsequent high-temperature sintering is high, the density is good, the physical property is reliable, the precision is high, the overall processing cost of the finished product is obviously reduced, the overall processing procedure is shortened, the effects of high finished product precision ratio to casting, low surface treatment cost and high material selectivity are realized, and personnel and equipment are greatly compressed.)

1. A powder injection manufacturing method for producing high-precision and high-quality knives and scissors is characterized in that: the method specifically comprises the following steps:

s1, mixing and granulating materials: firstly, alloy powder and a binder are put into an internal mixer for uniform mixing, stirring and internal mixing, then the mixed material after internal mixing is put into a granulator for granulation, and then the prepared feed is collected and stored;

s2, injection molding: adding the mixed material which is made into granules into an injection machine, simultaneously synchronously placing the cutter body to be manufactured into a mould of the injection machine, injecting the mixed material to the surface of the cutter body by the injection machine to realize molding, and obtaining a green blank with a required shape;

s3, catalytic degreasing: carrying out catalytic degreasing on the cutting blank body in an acid atmosphere at the temperature of 110-130 ℃ for 2-10 h;

s4, vacuum high-temperature sintering: placing the degreased blank in a vacuum sintering furnace for high-temperature sintering, wherein the sintering temperature is 1200-1500 ℃, the heat preservation time is 1-3 h, and after the heat preservation is finished, forcibly cooling to obtain a formed cutter blank;

s5, shaping and post-processing: and taking the formed cutter blank out of the vacuum sintering furnace, shaping and performing heat treatment on the formed cutter blank, cleaning and polishing the surface of the formed cutter blank after the treatment is finished, and then edging the formed cutter blank to obtain the finished cutter.

2. The powder injection manufacturing method for producing the high-precision and high-quality knife shear as claimed in claim 1, wherein the powder injection manufacturing method comprises the following steps: the S1 alloy powder comprises the following components in percentage by mass: mo: 1.5% -4.7%, V: 2.6.0% -6.0% and Cr: 15-17 percent of Fe, and the balance of Fe.

3. The powder injection manufacturing method for producing the high-precision and high-quality knife shear as claimed in claim 1, wherein the powder injection manufacturing method comprises the following steps: the mixed material in the S1 is powder, and the binder comprises the following components in percentage by mass: POM: 80% -90%, PP: 3% -15% and crystalline wax: 5 to 7 percent.

4. The powder injection manufacturing method for producing the high-precision and high-quality knife shear as claimed in claim 1, wherein the powder injection manufacturing method comprises the following steps: and when the internal mixer in the S1 is used for internally mixing the alloy powder and the binder, the temperature is 190 ℃, the internal mixing time is 45min, and the stirring speed is 13-17 r/min.

5. The powder injection manufacturing method for producing the high-precision and high-quality knife shear as claimed in claim 1, wherein the powder injection manufacturing method comprises the following steps: the acid used for catalytic degreasing of S3 is one of nitric acid or oxalic acid.

6. The powder injection manufacturing method for producing the high-precision and high-quality knife shear as claimed in claim 1, wherein the powder injection manufacturing method comprises the following steps: vacuum sintering low temperature stage 200 ~ 600 ℃ carries out negative pressure thermal degreasing to the idiosome among the S4, and sintering furnace bottom fixed mounting has an independent condensing vessel to the realization is collected the condensation of binder, and is simultaneously through adjusting the steerable binder desorption speed of condensation speed.

7. The powder injection manufacturing method for producing the high-precision and high-quality knife shear as claimed in claim 1, wherein the powder injection manufacturing method comprises the following steps: the forming cutter blank in the S5 can be subjected to surface cleaning and polishing through porcelain polishing and sand blasting.

Technical Field

The invention relates to the technical field of powder metallurgy, in particular to a powder injection manufacturing method for high-precision and high-quality knife and shear production.

Background

The metal powder injection molding technology is a novel manufacturing technology combining powder metallurgy and plastic forming technology. The preparation method comprises the steps of mixing the selected powder with a binder, granulating the mixture, and then performing injection molding to obtain the required shape. The polymer imparts its viscous flow characteristics to the mix, which aids in the uniformity of forming, cavity filling and powder packing. After forming, the binder is removed, and the degreased blank is sintered. Some sintered products may be subjected to further densification, heat treatment or machining. The sintered product not only has the same complex shape and high precision as the product obtained by the plastic injection molding method, but also has the physical, chemical and mechanical properties close to those of a forged piece, and the technical characteristics make the process technology especially suitable for mass production of small-sized, precise and three-dimensional metal parts with complex shapes and special performance requirements.

The finished product processed by the existing knife-shearing forming processing method has low precision, needs to be processed and then processed, has large configuration of the whole process personnel and equipment investment, higher corresponding cost, difficult control of the appearance of the product, reduced performance of the finished product due to process reasons, long production period of the product and low yield.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a high-precision high-quality powder injection manufacturing method for the production of a knife shear, and solves the problems that the finished product processed by the existing knife shear forming processing method has low precision, needs to be processed and then processed, has large whole process personnel configuration and equipment investment, has high corresponding cost and uniform product appearance, and is difficult to control.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: a powder injection manufacturing method for high-precision and high-quality knife and shear production specifically comprises the following steps:

s1, mixing and granulating materials: firstly, alloy powder and a binder are put into an internal mixer for uniform mixing, stirring and internal mixing, then the mixed material after internal mixing is put into a granulator for granulation, and then the prepared feed is collected and stored;

s2, injection molding: adding the mixed material which is made into granules into an injection machine, simultaneously synchronously placing the cutter body to be manufactured into a mould of the injection machine, injecting the mixed material to the surface of the cutter body by the injection machine to realize molding, and obtaining a green blank with a required shape;

s3, catalytic degreasing: carrying out catalytic degreasing on the cutting blank body in an acid atmosphere at the temperature of 110-130 ℃ for 2-10 h;

s4, vacuum high-temperature sintering: placing the degreased blank in a vacuum sintering furnace for high-temperature sintering, wherein the sintering temperature is 1200-1500 ℃, the heat preservation time is 1-3 h, and after the heat preservation is finished, forcibly cooling to obtain a formed cutter blank;

s5, shaping and post-processing: and taking the formed cutter blank out of the vacuum sintering furnace, shaping and performing heat treatment on the formed cutter blank, cleaning and polishing the surface of the formed cutter blank after the treatment is finished, and then edging the formed cutter blank to obtain the finished cutter.

Preferably, the alloy powder in the S1 comprises the following components in percentage by mass: mo: 1.5% -4.7%, V: 2.6.0% -6.0% and Cr: 15-17 percent of Fe, and the balance of Fe.

Preferably, the mixed material in S1 is in a powder form, and the binder includes, by mass: POM: 80% -90%, PP: 3% -15% and crystalline wax: 5 to 7 percent.

Preferably, when the internal mixer in S1 is used for internal mixing of the alloy powder and the binder, the temperature is 190 ℃, the internal mixing time is 45min, and the stirring speed is 13-17 r/min.

Preferably, the acid used for catalytic degreasing of S3 is one of nitric acid and oxalic acid.

Preferably, vacuum sintering low temperature stage 200 ~ 600 ℃ carries out negative pressure thermal degreasing to the idiosome in S4, and sintering furnace bottom fixed mounting has an independent condensing vessel to the realization is collected the condensation of binder, and the while is through adjusting the steerable binder desorption speed of condensation speed.

Preferably, the blank of the forming cutter in S5 may be subjected to surface cleaning and polishing by porcelain polishing and sand blasting.

(III) advantageous effects

The invention provides a powder injection manufacturing method for producing high-precision and high-quality knives and scissors. Compared with the prior art, the method has the following beneficial effects: the powder injection manufacturing method for producing the high-precision and high-quality knife scissors comprises the following steps of S3, catalytic degreasing: carrying out catalytic degreasing on the cutting blank body in an acid atmosphere at the temperature of 110-130 ℃ for 2-10 h; s4, vacuum high-temperature sintering: placing the degreased blank in a vacuum sintering furnace for high-temperature sintering, wherein the sintering temperature is 1200-1500 ℃, the heat preservation time is 1-3 h, and after the heat preservation is finished, forcibly cooling to obtain a formed cutter blank; s5, shaping and post-processing: taking the formed cutter blank out of the vacuum sintering furnace, shaping and heat treating the formed cutter blank, cleaning and polishing the surface of the formed cutter blank after the treatment is finished, edging the formed cutter blank to obtain a finished cutter, removing most of binder by catalytic degreasing in an acid atmosphere, ensuring good blank shape retention, ensuring high uniformity and density of finished product tissues after subsequent high-temperature sintering, reliable physical performance and high precision, obviously reducing the overall processing cost of the finished product, shortening the overall process, placing the degreased blank in a vacuum sintering furnace for high-temperature sintering, and performing forced cooling after heat preservation, thereby realizing net forming and high yield of the finished product, reducing the cutting processing of the finished product, reducing the processing difficulty of the manufacturing method on the complex structure of the small-size finished product, realizing the effects of high precision of the finished product compared with casting, low surface treatment cost and high material selectivity, the material waste is reduced, and personnel and equipment are greatly compressed.

Drawings

FIG. 1 is a process flow diagram for powder injection fabrication according to the present invention;

FIG. 2 is a comparative table of the powder injection molding composition index of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-2, an embodiment of the present invention provides a technical solution: a powder injection manufacturing method for high-precision and high-quality knife and shear production specifically comprises the following steps:

s1, mixing and granulating materials: firstly, alloy powder and a binder are put into an internal mixer for uniform mixing, stirring and internal mixing, then the mixed material after internal mixing is put into a granulator for granulation, and then the prepared feed is collected and stored;

s2, injection molding: adding the mixed material which is made into granules into an injection machine, simultaneously synchronously placing the cutter body to be manufactured into a mould of the injection machine, injecting the mixed material to the surface of the cutter body by the injection machine to realize molding, and obtaining a green blank with a required shape;

s3, catalytic degreasing: carrying out catalytic degreasing on the cutting blank body in an acid atmosphere at the temperature of 110-130 ℃ for 2-10 h;

s4, vacuum high-temperature sintering: placing the degreased blank in a vacuum sintering furnace for high-temperature sintering, wherein the sintering temperature is 1200-1500 ℃, the heat preservation time is 1-3 h, and after the heat preservation is finished, forcibly cooling to obtain a formed cutter blank;

s5, shaping and post-processing: and taking the formed cutter blank out of the vacuum sintering furnace, shaping and performing heat treatment on the formed cutter blank, cleaning and polishing the surface of the formed cutter blank after the treatment is finished, and then edging the formed cutter blank to obtain the finished cutter.

In the invention, the alloy powder in the S1 comprises the following components in percentage by mass: mo: 1.5% -4.7%, V: 2.6.0% -6.0% and Cr: 15-17 percent of Fe, and the balance of Fe.

In the invention, the mixed material in S1 is powder, and the binder comprises the following components in percentage by mass: POM: 80% -90%, PP: 3% -15% and crystalline wax: 5 to 7 percent.

In the invention, when the internal mixer in S1 is used for internally mixing the alloy powder and the binder, the temperature is 190 ℃, the internal mixing time is 45min, and the stirring speed is 13-17 r/min.

In the invention, the acid used for S3 catalytic degreasing is one of nitric acid or oxalic acid.

In the invention, the blank is subjected to negative pressure thermal degreasing at the vacuum sintering low-temperature stage of 200-600 ℃ in S4, an independent condensing container is fixedly arranged at the bottom of a sintering furnace to realize condensing and collecting of the binder, and the binder removal speed can be controlled by adjusting the condensing speed.

In the invention, the forming cutter blank in S5 can be subjected to surface cleaning and polishing through porcelain polishing and sand blasting.

And those not described in detail in this specification are well within the skill of those in the art.

Comparative experiment

According to a certain cutting and shearing forming processing method, a powder injection manufacturing method and the existing cutting and shearing forming processing method are respectively adopted to carry out comprehensive comparison experiments, and as can be seen from figure 2, the comprehensive index of the powder injection manufacturing method is 0.9 (the higher the comprehensive index is, the higher the comprehensive production efficiency is), and the comprehensive index of the existing cutting and shearing forming processing method is 0.6 (the higher the comprehensive index is, the higher the comprehensive production efficiency is), so that the comprehensive using effect of the powder injection manufacturing method is far higher than that of the existing cutting and shearing forming processing method.

In conclusion, most of the binder is removed by catalytic degreasing in an acid atmosphere, the blank has good shape retention, the finished product after subsequent high-temperature sintering has high uniformity and density, reliable physical performance and high precision, the processing cost of the whole finished product is obviously reduced, the whole process is shortened, the degreased blank is placed in a vacuum sintering furnace for high-temperature sintering, forced cooling is completed after the temperature preservation is finished, the net forming and high yield of the finished product are realized, the cutting processing of the finished product is reduced, the processing difficulty of the manufacturing method on the complex structure of the small-size finished product is reduced, the effects of high precision of the finished product, low surface treatment cost and high material selectivity are realized, the material waste is reduced, and personnel and equipment are greatly compressed.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.