JPH05364A - Manufacture of long preform by spray-deposit method - Google Patents

Abstract

PURPOSE:To prevent porosity in a long preform formed by spray-deposit method. CONSTITUTION:At the time of manufacturing the long preform 11 by slowly advancing a long hollow or solid collector 1 for the preform horizontally arranged which is penetrating a chamber 2 while rotating at low speed, a molten metal stream for preheating, is poured on the outer periphery of this collector 1 to make metal layer 8, and preheat the collector 1, and after that, by immediately depositing the spray stream 10, the development of porosity at the collector side is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a long preform by spray deposit.

[0002]

2. Description of the Related Art Generally, the spray deposit method is a method of atomizing a molten metal with an inert gas,
A method in which finely crushed droplets are rapidly solidified while being scattered and deposited on a collector to obtain a preform (form material) having a desired shape (for example, Japanese Patent Publication No. 54-29985 and Japanese Patent Publication No. 56-12220). JP-A-64-152
No. 64, etc.) and is characterized in that it has a uniform microstructure by rapid solidification, no macro segregation, and good workability and forgeability as compared with the ordinary casting method. There is. In addition, such a spray deposit method can reduce the porosity and obtain a high-density preform as compared with the spraying method in which a molten metal particle group is sprayed on the surface of the coating material to form a laminated coating, and the productivity is high. Has high characteristics. However, when such rapid solidification is extremely performed, porosity occurs and a high density preform cannot be obtained. In other words, the cause of this porosity is that if the cooling by the gas becomes too extreme, the preform
It is considered that the proportion of solid phase particles in the particles deposited on the slab becomes high, and the liquid phase and semi-molten particles filling the gaps between solid phase particles decrease, so the gaps between solid phase particles become porosity. In addition, when the temperature of the particles is relatively low, the particles are less likely to be flattened at the time of collision and form a portion that shadows particles that come later. However, if the temperature of the particles that come later is in a sufficiently high molten state, this shadow part can be filled, but if the temperature is low, it is thought that porosity will not be filled. As described above, the cause of porosity in the preform is considered to be related to temperature, but it is still unclear. For example,
In the case of manufacturing a tubular preform, a porosity layer may be generated in the vicinity of the tube collector. When this is analyzed, it is considered that the particles in contact with the collector have a low temperature, and porosity occurs due to the above reasons. Therefore, it is possible to preheat the tube collector. As this preheating method, high frequency preheating,
When plasma preheating is applied, discontinuity of preheating and a temperature difference in the longitudinal direction occur in the case of a tube-shaped long product, partial porosity still occurs, and a solid billet When joining the cladding layer to the collector,
There is a problem that a porosity layer is generated between the side and the deposited layer. On the other hand, in the above-mentioned Japanese Patent Laid-Open No. 64-15264, in a method of manufacturing a composite metal material using a spray deposit method, a separate preheating molten metal is plated before spray depositing for different metals. A method for producing a composite metal material is described, in which a coating layer is formed by flowing it down on a base material and a spray layer is deposited on the coating layer for different metals. The manufacturing method is similar to the method for manufacturing a general rolled clad steel, in order to increase the bonding force between the dissimilar metal and the base material, between the base material and the dissimilar metal,
For example, preheating molten metal to prevent carbon diffusion (eg,
(Ni) coating layer (so-called foil) is interposed, and boundaries between the sprayed particles may remain, so that porosity generation cannot be completely prevented. There is a problem that it cannot be applied to a hollow or solid preform.

[0003]

Therefore, the present invention was created in order to solve the above-mentioned various problems all at once, and the gist of the invention is to inject an inert gas toward the ceiling side of the chamber. A first container containing a molten metal for performing spray deposit is provided through an atomizer, receives a spray flow from the atomizer, and
In a spray deposit device in which a long preform collector that can rotate and move in the longitudinal direction is installed laterally through the chamber, the long preform is provided.
A second container supported in the chamber and containing the preheating molten metal is provided on the upstream side in the moving direction of the preheating melt, and the preheating molten metal is supplied from the wide pouring port of the second container. After pouring a metal stream to form a metal layer on the outer periphery of the collector, depositing the spray stream suppresses porosity on the collector side of the preform. It is in the method of manufacturing the shaku preform.

[0004]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The constitution of the present invention will be described in detail with reference to an embodiment apparatus shown in the accompanying drawings. FIG. 1 is a schematic view of an apparatus according to an embodiment of the present invention, and FIG. 2 is a side view taken along the arrow A in FIG. 1. This embodiment shows a spray deposit apparatus (so-called Osprey apparatus).
Are suitable for producing hollow or solid long tube-shaped preforms of ferrous or non-ferrous metals. In the figure, 1 is a long tube collector (S25
C) or a base material, which is laterally penetrated by the chamber-2 and is supported by collector-supporting stands 3 and 3 provided outside the chamber-2, which rotate at 5 to 500 rpm and It is designed to drive slowly from right to left in the middle. The collector or the base material 1 serves as a collector when manufacturing a hollow preform and serves as a base material when manufacturing a solid preform, but both are collectively referred to as a collector hereinafter. Inside the chamber-2, a preheating tundish 4 is tiltably provided on the upstream side in the moving direction of the collector-1, and on the ceiling side of the chamber-2, a downward flow is used for spray deposit. A container 5 such as a tundish or a crucible is provided. Below the container 5 is an atomizer-6.
Is installed. These tundish 4 and container 5
The molten metal 7 of the same quality (for example, SUS304) 7 is contained in, but the molten metal 7 contained in the tundish 4 is maintained at a slightly high temperature. And this tundish 4
The pour spout is made wide so that the metal layer 8 having a uniform thickness can be formed by pouring thinly on the outer periphery of the collector-1. The temperature of the metal layer 8 is measured by a thermometer such as a pyrometer (not shown) to adjust the tilt of the tundish 4 and control the pouring amount. And below the position where this tundish 4 is arranged,
An auxiliary straightening roll 9 is provided adjacent to the collector-1 to further smooth the metal layer 8 and prevent the metal flow from falling. Further, a preheater 14 may be attached on the upstream side of the tundish 4 (with respect to the moving direction of the collector-1), if necessary. A saucer 12 lined with a refractory material is provided immediately below the tundish 4 so as to receive the pouring metal that could not be captured by the collector-1. Further, the spray stream 10 that cannot be captured by the collector-1 is recovered by a dust collector (not shown) through the exhaust gas bench rotor 13 as in the case of a normal spray deposit device. Next, the operation of the apparatus of this embodiment will be described. First, a thin preheated molten metal flow is poured from the wide pouring port of the tundish 4 onto the outer circumference of the rotating collector-1, and the entire circumference is smoothed. The metal layer 8 is formed. At this time, if necessary, an auxiliary straightening roll 9 is used to eliminate the unevenness of the layer surface and prevent the porosity layer due to the unevenness. As a result, the collector-1 is evenly preheated in its axial direction. The location of the preheated collector-1 is moved directly below the spray deposit container 5 to deposit the spray stream 10. In addition, this spray style 10
Is dispersed in the chamber-2 and mixed in the tundish 4, but since it is a molten metal of the same quality, no trouble occurs. As a result, the metal layer 8 previously covered by the collector-
1 is preheated to prevent the generation of porosity, and even if a porosity layer is formed by spray deposit,
The metal layer 8 can be dissolved and removed.

[0005]

According to the present invention, since a collector or a base material for forming a hollow or solid preform is provided laterally through the chamber, a long preform can be obtained. In addition, since the metal layer poured from the wide pouring port of the tundish is pre-formed on the outer periphery of the collector or the base material to preheat the collector or the base material, the metal layer surface has unevenness. In addition, it is possible to produce a long preform having good quality by preventing the occurrence of porosity by uniformly heating even though it is long.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a side view taken along the arrow A in FIG.

[Explanation of symbols]

1 collector, 2 chambers, 4 tundish,
5 container, 6 atomizer, 8 metal layer, 10 spray flow, 11 preform

Claims (1)

Claim: What is claimed is: 1. A first container provided with molten metal for spray depositing is provided on a ceiling side of a chamber through an atomizer that ejects an inert gas, and A long preform collector, which receives the spray flow from the atomizer and is capable of rotating and moving in the longitudinal direction, is installed horizontally through the chamber.
In the depositing device, provided on the upstream side in the moving direction of the long preform collector is a second container supported in the chamber and containing a preheating molten metal.
A preheating molten metal flow is poured from a wide spout of the second container to form a metal layer on the outer periphery of the collector, and then the spray flow is deposited to collect the preform collector. A method for manufacturing a long preform by spray deposit, which is characterized by suppressing side porosity.