JPH0563547B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention is a zinc alloy-plated iron that has excellent heat resistance, corrosion resistance, adhesion, and workability, and is produced by applying hot-dip zinc alloy plating to a ferrous metal wire made of iron, steel, or an iron alloy. This relates to metal wires. (Background technology) In recent years, heat-resistant steel core aluminum stranded wire (hereinafter referred to as ACSR) is used. The iron alloy wire used for such heat-resistant ACSR is usually a steel wire for ACSR coated with Al and galvanized. However, although Al coating has excellent corrosion resistance and heat tightness, it is expensive, and zinc plating is
Although it is inferior to the coating, it improves the corrosion resistance as an ACSR and is inexpensive, but as previously reported, heating progresses the diffusion of the Zn-Fe interface.
Due to the formation of Kirkendall voids, plating peels off (Miura et al.; Journal of the Japan Institute of Metals, 39 (1975) -
903), it had the disadvantage of low heat resistance. It was found that adding Al to the Zn plating bath was effective in improving this heat resistance, but it was found that adding Al to the Zn plating bath was effective.
If only Al alloy is used, the molten metal will be severely oxidized due to the influence of Al, and as a result, oxides will be formed on the plating bath surface, and an oxide film will be drawn into the plating area during melt plating.
It had the disadvantage of poor appearance and poor uniformity of plating. In addition, Zn-Al binary alloy alone has poor workability, for example, when an acute angle bending test is performed, cracks occur in the plating, and it is difficult to perform after-drawing. (Disclosure of the invention) In order to solve the above-mentioned problems, the present invention provides Zn
- This was achieved after studying the addition of various other elements to Al alloys, and it improves the flow, wettability, and reactivity of the plating bath during hot-dip galvanizing, and improves surface condition, adhesion, and processability. It is an object of the present invention to provide a heat-resistant zinc alloy plated iron-based metal wire with improved properties, good appearance, and good uniformity. The present invention provides, on the outer periphery of iron, steel or iron alloy wire,
Contains Al0.2~14%, Be0.0001~0.01%, Pb
A heat-resistant zinc alloy plated ferrous metal characterized by being made by melt-plating a Zn alloy containing 0.03% or less Zn and unavoidable impurities in a temperature range of 10° to 100°C above the melting point. It is a line. The iron, steel or iron alloy wire in the present invention is made of iron, carbon steel, special steel to which other elements are added, or iron alloy. In particular, Fe--Ni alloys with a small coefficient of thermal expansion, which have been attracting attention recently, can also be used. This alloy includes an alloy containing 35 to 42% Ni;
Or this alloy contains Cr, Mo, Si, Mn, C, Nb,
An alloy is used in which a total of 0.2 to 10% of one or more elements selected from the group consisting of Co, Al, Mg, and Ti is added.
-It is expected to have the effect of strengthening the Ni-based alloy wire or not increasing the coefficient of thermal expansion. Generally, iron-based metals and Zn are heated during melt-plating of Zn or after Zn plating to generate three types of compound layers {γ (gamma), δ (delta), and ξ (zeta)}. Such Fe-Zn compounds cause deterioration in toughness, and, for example, when heated at 300° C. for 100 hours, vibration fatigue strength decreases. Also at 300℃
After heating for 100 hours, the torsion value decreased significantly, and in extreme cases, peeling occurred at the interface of the grown alloy layer. In order to suppress the growth of this compound layer, in the present invention, 0.2 to 14% of Al is added to Zn. Al0.2~14 to Zn
% is added to suppress the growth of a compound layer of Fe and Zn alloy during melt plating or heating after plating, and if the Al content is less than 0.2%, it is not effective in suppressing the compound layer. When the Al content exceeds 14%, not only the compound layer suppressing effect is saturated, but also Zn
- This is because the viscosity of the Al alloy molten metal becomes high and the appearance defect upon melt-welding becomes significant. The amount of Al is preferably 0.2 to 1.0% and 4.5
There are two ranges of ~5.5%, the most preferred being
In the range of 0.2 to 1.0%, if the Al amount exceeds 1.0%, Zn
- Dross generation due to oxidation of Al in molten Al alloy,
Al ₃ Fe is generated violently due to the reaction with the iron-based metal wire, so care must be taken to control the Al component. or
When the Al content is 4.5 to 5.5%, although it is difficult to control the Al composition, it becomes eutectic as a Zn-Al alloy, has a low melting point, and can be plated at a lower temperature, giving a positive effect to iron-based metal wires. This has the advantage of reducing thermal effects. In addition, Be in the Zn alloy suppresses oxidation of the molten metal during melt welding, improves the flow of the molten metal, and improves wettability.
Improves plating surface condition, adhesion, and workability.
The reason why the amount of Be was specified as 0.0001 to 0.01% is that Be is Al
Increasing the amount as the amount increases is more effective in improving the surface condition, but as the amount added increases, the cost increases, so it is preferable to keep it below 0.01%, and if the Be amount is less than 0.0001%, it will prevent oxidation of the molten metal and improve the flow of the metal. This is because the effect is not sufficient. The reason why Pb was suppressed to 0.03% or less is that although Pb exceeding 0.03% improves the flow and wettability of the plating bath, it coarsens the crystal grain size of the plating and deteriorates adhesion and workability. be. In particular, Zn plating with Pb exceeding 0.03% causes the plating to harden over time, and for example, when such Zn-Al alloy plated wires are twisted together, cracks occur during the preform of the twisting. Also, set the melting temperature to the melting point of the alloy plus 10°.
The temperature range was set at 100℃ because it is difficult to maintain the bath temperature below +10℃, and a Zn and Fe compound layer is formed when the temperature exceeds +100℃.
This is because the heat resistance targeted by the present invention cannot be obtained. The higher the temperature of the plating bath is within the above-mentioned range, the better the adhesion will be, and no cracking will occur during subsequent processing. However, as the bath temperature rises, the amount of glazing decreases, making cooling difficult, and in extreme cases, a water-cooled pattern will appear, making the product unworthy of commercial value in terms of appearance. The most preferred temperature is the highest temperature without deterioration of appearance. The results will be better if the amount of Be added is increased as the Al concentration in the plating bath increases.
If it exceeds 14%, the surface condition of the mating will deteriorate. Next, a method for manufacturing the zinc alloy plated iron-based metal wire of the present invention will be described. The figure is a sectional view showing an example of an apparatus used for melt plating of an embodiment of the plated wire of the present invention. In the figure, 1 has been subjected to degreasing using a lead bath, continuous furnace, electrolytic method, etc., pickling using hydrochloric acid, sulfuric acid electrolysis, etc., flux treatment, or reduction treatment using reducing gas, as in the usual hot-dip galvanizing method. The iron-based metal wire is immersed in a Zn alloy plating bath 2 using a sinker roll 3 and then pulled up through a squeezing device 4 to form a zinc alloy-plated iron-based metal wire 5. As the flux, a mixed flux of zinc chloride and ammonium chloride is usually used. Furthermore, H ₂ gas is suitable as the reducing gas. The iron-based metal wire 1 that has entered the Zn alloy plating bath 2 containing 0.2 to 14% Al in this way is transferred to the plating bath 2.
Immediately after contact with the wire, an intermetallic compound layer such as Fe ₂ Al ₅ is formed on the wire surface. This intermetallic compound formation prevents the diffusion of Fe and Zn during subsequent heating, and exhibits the effect of improving heat resistance. Note that unlike normal galvanizing, the influence of the immersion time in the plating bath is small, and there is no change in the heat resistance etc. of the plating even if the immersion time is varied within the range of 5 to 60 seconds. In this case, Be in the plating bath suppresses oxidation of the molten metal, improves melt flow, and improves wettability, so there is no unplated plating, the surface is in good condition, adhesion is good, and workability is improved. Excellent uniform plating lines can be obtained. As the diaphragm drawing device 4, ordinary galvanized graphite powder or the like can be used.
There are no particular restrictions. Example 1 Using the apparatus shown in the figure, a 3.0 mmφ steel wire was hot-dipped in a plating bath having the composition shown in Table 1. Electrolytic pickling with 30% sulfuric acid was used for pickling. After pickling, it was introduced into plating bath 2 through a reduction furnace using ammonia converted gas. The plating bath temperature was 20° C. above the melting point, and plating was performed at a linear speed of 30 m/min. Appearance of the obtained hot-dip galvanized steel wire, 1000 at 260℃
Table 1 shows the results of investigating the presence or absence of peeling of the plating after heating for a certain period of time and the cracking of the plating during the bending test.

[Table] 〓

Claims (1)

[Claims] 1 Al0.2-14% on the outer periphery of iron, steel or iron alloy wire,
A Zn alloy containing 0.0001 to 0.01% Be, suppressing Pb to 0.03% or less, and the balance Zn and unavoidable impurities is melt-plated at a temperature range of 10° to 100°C above the melting point. Features: Heat-resistant zinc alloy plated iron metal wire.