JPH06212388A - Method for activating projecting material for mechanical plating - Google Patents

Abstract

PURPOSE:To reactivate the deteriorated projecting material for zinc-iron mechanical plating by heat-treating the material under specified conditions. CONSTITUTION:The projecting material for mechanical plating obtained by coating the core of iron or iron alloy with a zinc alloy layer and with the adhesion power to the material to be treated decreased after long use is heat- treated at 300-550 deg.C for 10-60min. As a result, the projecting material with the adhesion power decreased is reactivated, and the service life of the projecting material is prolonged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical plating method using a zinc-iron based blasting material having an iron core, which is a dry rust preventive method, and particularly to reactivating a blasting material whose adhesion ability is deteriorated. It is about the method.

[0002]

2. Description of the Related Art A dry type in which a projection material for mechanical plating, in which a zinc alloy layer is coated around the core of iron or an iron alloy, is projected onto the surface of an object to be processed to form a zinc alloy layer on the surface of the object. The rust prevention method has been attracting attention as an alternative to the galvanizing method, which has various problems such as pollution. Such a shot material is prepared by adding iron powder having a predetermined particle size to molten zinc, stirring the mixture, maintaining the state at a predetermined temperature for a predetermined time, and then cooling,
Generally, it is manufactured by crushing and sizing. It has been found that heat treatment of the sized particles at a temperature of about 500 ° C. raises the altitude, and the composition is homogenized to increase the ability to adhere to the object to be treated. It is proposed as No. 4-61427.

[0003]

However, this blast material has the same adhesive ability as other blast materials as it deteriorates with use, and even if it does not change much in appearance, this deterioration is limited. After passing, the only option was to discard it. The biggest drawback of this method is that it must discard such deteriorated materials, and if it can be reactivated by some method, it seems to be very popular. Under such circumstances, the present invention has found a method for this activation.

[0004]

SUMMARY OF THE INVENTION Under the above problems, the present invention provides a mechanical play in which a zinc alloy layer is deposited around the core of iron or an iron alloy whose ability to adhere to an object to be treated deteriorates. A projection material for coating at 300 to 550 ° C, 10
Provided is a method for activating a projection material for mechanical plating, which is characterized by performing heat treatment for 60 minutes.

[0005]

The zinc-iron blasting material is useful as a blasting material because it has an iron nucleus with a high specific gravity and has a hardness that is easily destroyed during a collision. This is because the surface has properties such as an angular shape. It can be easily imagined that the hardness is maximum in the iron core portion and becomes lower toward the surface layer. In addition, it can be easily imagined that the product immediately after production has an angular surface due to the particles rubbing against each other during the processes such as disintegration and sizing.

When this is projected many times with use,
It is easy to predict that the surface of the zinc layer will have a rounded corner due to the fracture and forging effects, and will have a nearly spherical shape. Therefore, if this shape can be recovered by some method,
It is clear that its adhesive capacity can be restored. Under such an idea, when the deteriorated shot material is heat-treated in the same manner as in manufacturing, its hardness and surface shape can be recovered by the annealing and diffusion effects.

[0007]

EXAMPLE An equivalent weight particle size of 40 to 60 to molten zinc in a container
After iron powder of mesh was added and stirred to alloy, it was taken out of the container, cooled, pulverized and sieved to produce a projection material having a particle size of 27 to 60 mesh. Then, this projection material
After heat treatment at ℃ for 10 minutes, iron plate (S45C,
(20 × 20 × 2.3 mm) was repeatedly projected 10 times.

Projection conditions Projection amount 500 g Projection pressure 5 Kg / cm ² Projection distance 140 mm

After the projection material having a reduced adhesion ability by repeatedly projecting 10 times is heat-treated at 300 to 600 ° C. for 10 to 60 minutes, it is repeatedly projected 10 times again on the same iron plate under the above-mentioned projection conditions, and the number of projections and the amount of deposition are carried out. I investigated the relationship between. The results are shown in Fig. 1.

As is apparent from FIG. 1, it is understood that the amount of adhesion decreases with the number of projections in the number of projections 1 to 10 in the first stage. This is probably because the shot material repeatedly collides at a high speed, and the surface is smooth and spherical due to the forging effect and surface work hardening. However, it can be seen that if the shot material deteriorated in this way is heat-treated again, the adhesion amount is recovered (rather, it is higher than that immediately after manufacturing). This is considered to be because recrystallization and homogenization of the composition of the alloy layer are achieved by the heat treatment again.

Table 1 shows the relation between the heat treatment conditions for the second time and the adhesion amount. As is clear from this, 300
At 10 ° C for 10 minutes, the recovery effect is small. Therefore, in the case of 300 ° C., it takes about 60 minutes. On the other hand, 600
On the contrary, at 10 ° C. for 10 minutes, the adhered amount decreased. This is probably because the hardness becomes too high and it becomes brittle. From these, it can be said that 500 ° C. and 10 minutes are ideal conditions.

[0012]

[Table 1]

[0013]

As described above, according to the present invention, the blast material whose adhesion ability has deteriorated with use can be reactivated, so that the blast material has a long life and is economical.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the number of times of projection and the adhesion amount.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomohiro Aisaka 7 Tsukiko Sakaemachi, Okayama City, Okayama Prefecture Dowa Iron & Powder Co., Ltd.

Claims (1)

[Claims] 1. A projection material for mechanical plating, in which a zinc alloy layer is adhered around a core of iron or an iron alloy whose adhesion ability to an object to be treated has deteriorated with use of 300 to 55.
A method for activating a projection material for mechanical plating, which comprises performing heat treatment at 0 ° C. for 10 to 60 minutes.