JPS60228073A - Material for precision wet shotblasting - Google Patents

Abstract

PURPOSE:To properly remove burr from a narrow portion and clean up a surface, by causing a synthetic resin for a mechanical construction to firmly cling in an irregular form to the peripheral surface of each of fine natural glass grans, so as to provide a shotblasting material of prescribed grain size and specific gravity. CONSTITUTION:A synthetic resin 2 for a mechanical construction is very firmly bonded in an irregular form to the peripheral surface of each of fine natural glass grains 1 so as to provide a precision wet shotblasting material which has an average grain size of 0.5mm. or less, preferably 0.2-0.3mm., an average specific gravity of 1.5 or less and a Rockwell hardness of M-80 or more and is very appropriate to remove burr from a narrow portion and clean up a surface.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the invention] (Industrial field of application) The invention relates to a projectile material for precision wet plastic processing.

(Prior art) De-sticking and cleaning of metal pots, especially ferrous metals,
Injection processing (or blasting) is used for the purpose of deburring after machining, surface cleaning, and pretreatment for surface treatment, and the blasting material and 17 are used to inject iron-based full-area particles such as steel shot grids, Non-ferrous metal particles, various artificial abrasive materials commonly referred to as abrasive grains, natural silica sand, alumina, etc. are commonly used.

7. When blasting molded products of light metals such as copper, zinc, aluminum, etc. or synthetic resins, the surface of the workpiece may be damaged if the blasting material is sharp and hard, or is fragile. To avoid unnecessarily deforming or damaging the material, so-called natural soft grids and projection materials made from various synthetic resins are used.

In blasting, in order for the process to be effective, the blast material must have certain mechanical properties, such as mechanical strength, surface hardness, and impact resistance. When blasting is applied to plastics or synthetic resins, the blasting material is the same as the blasting materials listed above (in addition to the general properties listed in 7), it can also be used to remove flakes without damaging the surface of processed products such as soft metals and synthetic resins. Alternatively, those that can be used to remove only foreign matter or to clean the surface are dehydrated.

For example, fix I, C, and chips on a lead frame (7
, pan cage made of synthetic resin (7 pieces).

C. Taking the case of cleaning a mold as an example, in this case, as shown in FIG. , a synthetic resin adhesion-resistant residue e is formed on the lead frame. Conventionally, these Paris d and adhesion-resistant residue e(l
-1i, 2001U degree alumina abrasive grains were removed by wet projection [7].

(Solution of the Invention (Problem to be Solved by 7)) Although the adhesion residue e and the paris on the contact part can be removed, the protruding part of the paris (2) is slightly 1.
<It was harshly ground, and at the same time, the surface of the pan-cairn part also became matte, resulting in [7 grinding], which had the disadvantage of lowering the product value. As in the above-mentioned example, if the part of the workpiece to be blasted that can be finished with the Dp process is fine, the disadvantage described in 1 above will occur. In addition, if soft glint is used, natural soft gris is made from corn cobs, walnut shells, cherry seeds, etc., and when wet processed, it swells with water and becomes unusable.

Particles of synthetic resins that are already available, such as those made large in order to produce processing effects (particle size 0. !; m
For example, the sharpness of fine parts such as the corners of the lead frame is insufficient (2 lines cannot be separated).

Furthermore, when synthetic resin particles are used as a projectile material in a mixed method, there are the following drawbacks. That is, commonly used synthetic resins (styrene vinyl chloride, polyamide, etc.) have a specific gravity in the range of 0/ to /, ri) are rare, and when trying to suspend synthetic resins other than polycarbonate and polyacetal, which are synthetic resins for machine structures, in water, E7 does not easily settle even in still water, and if there is a water flow, floating above the flowing water,
Not easily agitated. (7. When using wet method,
In blasting, uniform distribution of water and blasting material is a necessary condition to maintain uniformity of force.

This invention was developed in view of the fact that L7 often settles in liquid.
The purpose is to provide a projection material for precision wet blasting that is particularly suitable for use with precision wet blasting projection material and T7, and which can be supplied at a low cost. shall be.

[Invention, composition of invention]

(Means to Solve the Problem) This precision wet blasting ladle is made of fine grains of natural clast with a synthetic resin for mechanical structure shaped irregularly around the outer periphery of the fine grains of natural glass. , average particle size D: 0.3 wh
Ja 'T t, < HO, 2~0.3N+, and the average specific gravity is /,,! It is characterized by being on the ik.

(Example) The projection side for wet blasting according to the present invention is made of natural glass (i.e., natural glass (i.e., from an active volcano) as shown in FIG. The ejected acidic bath rock is rapidly cooled and solidified into a glassy substance, and the gas escapes and forms a porous igneous rock (commonly called pumice). Strongly resistant to shaping and adhesion [7: Average grain size is 0.5M or less, preferably 1.
< is 0.2~0.3 M f A! , the average specific gravity is /,
It honors the composition of 3 or more.

In order to make the projectile material for wet blasting according to the present invention, first, a camplink material is made to adhere to a fine-grained outer cylinder of natural crow with a particle size of 0.3 II/ or less, and then Mix well with synthetic resin for machine structures [7. Next, extrude using an extruder] 2. Cut the extruded material to make pellets: Place the pellets at -SO℃~-/2°C. ,
It is made by quickly freezing it and then crushing it.

In addition, in the above manufacturing method, Amionlan is used as the tip of camplik material (7, as a synthetic resin for machine structure, the specific gravity is 43 or more, the Rockwell hardness is M-#fO or more,
Use thermoplastic or thermosetting resins such as polyacetal, polycarbonate, etc., which have extremely low water absorption (7) and rapid cooling means (7) use liquid nitrogen or liquid oxygen.

(Function) The projectile material for wet blasting according to the present invention has a vaporized structure (7. When making it, firstly, a camping material is applied to the outer periphery of the fine grains of natural clast to prevent adhesion, and then the material is machined. However, the surface of the fine particles is porous and the camping material is even more resistant to adhesion. The bond with the material is extremely strong and the average specific gravity is
A mechanical camphor that is better than Ushio.

Because it is combined with advanced synthetic resin, the specific gravity is the lowest /, 3
It is possible to adjust up to θ and above, and when performing wet processing,
Since the shot material does not float to the surface of the liquid, there is no need to take any particular settling means, and mixing with the liquid is uniformly performed.

〔Effect of the invention〕

This invention has a synthesis method such as steaming7, and the natural grains are selected to have a grain size of 03 7 or less, and the average grain of the shot material is 0.5 NI h or less. 2〈is 0.2
Since it is ~0.3M and 7, it is particularly suitable for removing lead frame punctures and particles of synthetic resin protruding between the lead frame and the lead frame. Also, cut the material extruded from the extruder to make pellets, and heat the pellets to θ℃ with liquid nitrogen or liquid oxygen.
−／′? Because it is rapidly frozen at 5℃'t, it becomes lumpy, and because it is crushed, the synthetic resin for the mechanical structure around the outer surface of the natural crow fine grains is never spherical, and the shape shown in Figure 1 is 1.
It is irregularly shaped and 61! Rockwell hardness #
Since M- is 0 or more, when this is used as a projection material, it is possible to remove burrs in detail and clean the surface well.For example, as shown in Figure 2 (B), the burr d1 in Figure 1 (A)
The adhesion-resistant residue θ is completely removed, the package is not abraded to the extent that it becomes matte, and a layer of agent is applied to give it a glossy appearance. So[
7. When mixed with liquid and blasted with air, the particle size of the blasting material is 0.3 M-1 or more, preferably (7 or 0) ~ 03 mh1.
Synthetic resins, such as polycarbonate and polyacecool, have a specific gravity of /, 3 ~ /, g, so when combined with natural glass fine particles, the specific gravity of the particles is at least 7.3 ~
Since it is perfectly adjusted between 20 and 20, it settles well in the liquid and produces a uniform blasting material, and the natural glass fine particles and the synthetic resin for machine structures are better bonded [2. It is truly suitable for precision wet blasting. However, since natural crow is used, an extremely inexpensive projectile material can be obtained.

Related to Hiroshi This invention is based on the use of natural crow fine particles in place of the artificial crow pieces in the invention of the projecting material for coffin-tight wet blasting, which is the first invention of %Gan Sho 57-/7 Zo 75/7. This is an invention in which the main parts of the matters essential to Park and Seong of the first invention are combined with the main parts of the matters essential to the synthesis.

[Brief explanation of the drawing]

FIG. 1 shows fine grains of precision wet-plast natural glass according to the present invention, and D shows the particle size, respectively. that's all

Claims (1)

[Claims] The mechanical structural synthetic resin 2 is irregularly shaped and strongly adheres to the outer periphery of the fine grains of natural crow (7), and the average particle size is preferably 0.5 μ or less [7 or 0.2 ~0.3 W and an average specific gravity of 45 or more.