JPS59226180A - Production of al coated steel wire - Google Patents

Abstract

PURPOSE:To prevent seizure in drawing and to improve surface quality by coating Al on a steel wire in an extruder then heating the wire under specific conditions to accelerate oxidation of the outside surface. CONSTITUTION:A steel wire 1 let off from a supply device 2 is preheated by a heater 3 and thereafter Al is coated around the same in an extruder 4 and the wire is extruded as an Al-coated steel wire rod 5. The extruded material 5 is heated to <=600 deg.C in a heating oxidation furnace 6 or is exposed in the amt. in the range of the temp. T( deg.C) and time (t) (second) having the relation 5500/ (273+T)-7>=lnt to accelerate the oxidation on the wire surface and thereafter the wire is cooled in a cooling tank 7 and is coiled on a coiler 9 via a capstan 8. The excellent lubricating characteristic in succeeding drawing is thus obtd. and seizure is prevented.

Description

Detailed Description of the Invention: This relates to a method of manufacturing an A4 corroded steel wire whose circumference is coated with Hll or H1 alloy (hereinafter simply referred to as J) by extrusion coating and wire processing. It is.

(Background Art) Conventionally, when manufacturing HL9 steel wire by extrusion, cooling was performed by a method such as water cooling immediately after extrusion. This is because Al after extrusion is exposed to high temperatures and is easily damaged, reducing its commercial value. However, because it is rapidly cooled after extrusion, the A4 surface has an extremely fresh surface. For this reason, it has a large coefficient of friction with the tool during the subsequent wire drawing process, and is very likely to seize during processing, resulting in scratches and deterioration of surface quality.

(Disclosure of the Invention) The present invention has been made in order to eliminate the above-mentioned drawbacks.
The purpose of the present invention is to provide a method for producing an Al-coated steel wire with good surface quality without seizure by promoting the formation of an oxide film on the wire surface after extrusion and improving lubricity during wire drawing. It is something.

The present invention provides a method for manufacturing a hl-coated steel wire by extrusion coating and then wire drawing, in which, after extrusion,
The extruded material was heated at a temperature of 600°C or lower, and the temperature (T'C) and time (
This is a method for producing an Aβ-coated steel wire, which is characterized in that the oxidation of the outer surface is promoted by expanding the Aβ-coated steel wire into the atmosphere within a range of 2 seconds or by actively heating it in an oxidizing atmosphere.

In the present invention, A! The core material of the coated steel wire is iron, carbon steel, alloy steel with other alloying elements added, iron alloy (e.g. Ni33~
45%, low expansion coefficient Fe-Ni alloy, etc.)
These shells are made of ferrous metals such as aluminum or aluminum alloy.

Extrusion devices used in the present invention include, for example, a billet type extruder consisting of a container and a ram, and a friction-driven extrusion device consisting of a drive wheel and a fixed shoe block.
Conform device), friction-driven extrusion device (Wire Jo) consisting of opposing drive caterpillars and fixed walls on both sides.
urnal, April 1976 issue, P, 64. Any method such as a linex device) may be used.

Hereinafter, the present invention will be explained by way of examples using the drawings. The figure is a block diagram for explaining an embodiment of the method of the present invention.

In the figure, reference numeral 4 denotes an extrusion device, into which the steel wire 1 extruded from the supply device 2 and preheated by the heating device 3 is inserted, and the periphery of the steel wire 1 is coated with Al to form an AI-coated steel wire (
Hereinafter, it is extruded as 5 (referred to as extruded material).

The extruded paulownia 5 is heated at an appropriate temperature and time in a heating oxidation furnace 6 at the exit of the extrusion device N4 to promote oxidation of the wire surface, cooled in a water cooling tank 7, and wound up in a winder 9. 8 is a capstan.

This promotion of oxidation on the surface is to generate oxidation compounds suitable for wire drawing on the J surface, and may be carried out either continuously in the extrusion process as shown in the figure or in a batch process in a separate process. . A continuous type is preferable due to the manufacturing process. In addition, methods for promoting oxidation include exposing the product to the atmosphere at a high temperature after extrusion, or actively heating it in a heating furnace in an oxidizing atmosphere (e.g., in the air, with high concentration of oxygen, etc.). But it's okay.

The heating temperature is preferably as high as possible within a range that does not adversely affect the core steel wire, and a temperature range of 600°C or less is preferable. In the range exceeding 600°C, the strength of the wire decreases.

The inventor also found that the longer the exposure time or heat treatment time is within the range permitted by the manufacturing conditions, the better the results, and that the temperature and time should be within the range shown by the following formula (l). This became clear from the experience of others.

5500--7 ”a In t-[1)273+
T However, T: temperature ("C) t: time (seconds) (1) In a range outside the equation, the effect is low, and the effect of improving seizure during wire drawing becomes low.

When exposed to the atmosphere or subjected to heat treatment according to the present invention, oxidation of the extruded material's surface is promoted and the surface is covered with an oxide film, which provides excellent lubrication properties during subsequent wire drawing processing and improves sintering properties. Since no sticking occurs, surface defects such as scratches do not occur, and the surface quality of the product is improved (Example) Using the production line shown in the figure, the A4 cross-sectional area ratio
A 0% AI coated steel wire was produced.

A 6.7 mmφ C060% steel wire was used as the steel wire, and an Aβ-coated steel wire with an outer diameter of 8 was extruded at a linear speed of 50 ml'v) using an extrusion device 4, and three types of extrusion hole treatment were performed. I did it.

■ After extrusion, it was extracted for 18 seconds and cooled with water (conventional example).

■ After extrusion, saw out in the air for 12 seconds and then cool in water (
present invention).

(2) After extrusion, it was heated in the air at 400°C for 12 seconds and then cooled with water (this invention).

The A4 wire rod produced under these conditions was drawn to 4.1πmφ using a continuous wire drawing machine, using Vinuraquip's forced lubrication die and a powdered solid lubricant mainly composed of calcium stearate. did.

The results of investigating the amount of wire drawing until seizure occurred during wire drawing are shown in Table IK.

Table 1 From Table 1, it can be seen that in the case of the present invention, the frequency of occurrence of burn-in is much lower than that of the conventional example, and that burn-in does not occur in processing method ①.

(Effects of the Invention) The method for manufacturing a coated steel wire with A of the present invention configured as described above has the following effects.

After extrusion, the extruded material is heated at a temperature of 600°C or less at a temperature (T'C) and a time (
(seconds) or actively heated in an oxidizing atmosphere to promote oxidation of the outer surface.
1. Since the formation of a surface oxide film is promoted, it has excellent lubrication properties during the subsequent wire drawing process, and the frequency of seizure occurrence is greatly reduced, making it possible to produce AI-coated steel wire with good surface quality and high yield. obtain.

[Brief explanation of the drawing]

The figure is a block diagram for explaining an embodiment of the method of the present invention. DESCRIPTION OF SYMBOLS 1... Steel wire, 2... Supply device, 3... Heating device, 4... Extrusion device, 5. hl coated steel wire rod (extrusion material),
6. Heating oxidation furnace, 7. Water cooling tank, 8. Gear punutan, 9. Winding machine.

Claims (1)

[Scope of Claims] +11 In a method of manufacturing a coated steel wire by extruding it into an extrusion coating and then wire-drawing the wire, the thickness is 7≧ln.
It is characterized by promoting oxidation of the outer surface by expanding it into the atmosphere within a range of temperature (T"C) and time (in seconds) having the relationship t, or by actively heating it in an oxidizing atmosphere. A to do
1. Method for manufacturing a retained steel wire. +21 AA? The method for manufacturing an All-coated steel wire according to claim 1, wherein the circumference of an Al-coated steel wire iron, steel or Fe-Ni alloy core material is coated with Al or h1 alloy.