JPH05171363A - Stainless steel for expansion antenna - Google Patents

Abstract

PURPOSE:To provide an antenna material excellent in the corrosion resistance and the workability, inhibiting rust during use as an antenna, maintaining high quality appearance and excellent in the workability such as the rollability and the weldability at the time of producing an antenna. CONSTITUTION:This stainless steel for an expansion antenna consists of <=0.05% C, <=1.0% Si, <=2.0% Mn, <=0.05% P, <=0.001% S, 9-14% Ni, 22-24% Cr, 1-2% Mo, 0.1-0.2% Cu, 0.1-0.2% N and the balance Fe with impurities.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to stainless steel for telescopic antennas, which is preferably used as a material for telescopic antennas used in automobiles and the like.

[0002]

2. Description of the Related Art Conventionally, as a material for a telescopic antenna used in an automobile, for example, austenitic stainless steel No. 1 in Table 1 is used. SUS with the chemical composition shown in column 1
304 is often used.

[0003] This SUS304 is work-hardened by being subjected to cold drawing to impart toughness, and is a relatively inexpensive material among austenitic stainless steels, so that it is widely used as a material for elastic antennas. Has been adopted.

Further, No. 1 in Table 1 having improved corrosion resistance of the above-mentioned SUS304. SUS31 with chemical composition shown in column 2
5SN is also used in part.

[0005]

However, in the above-mentioned conventional austenitic stainless steel for a telescopic antenna, when the material itself or the welded portion is subjected to cold working such as pipe drawing, or surface polishing is performed. When it is received, processing-induced martensite occurs and corrosion resistance decreases, so rust may occur due to a wet environment or salt damage while using it as a stretchable antenna, and the appearance is damaged. However, there is a problem that expansion and contraction may not be smooth, and it has been a problem to solve such a problem.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is excellent in workability such as roll formability and weldability when manufacturing a telescopic antenna, and the material itself and It is an object of the present invention to provide stainless steel for stretchable antennas, which is excellent in corrosion resistance in which rust is unlikely to occur in the welded portion.

[0007]

The stainless steel for a telescopic antenna according to the present invention is, by weight%, C: 0.05% or less, Si: 1.0% or less, Mn: 2.0% or less, P:
0.05% or less, S: 0.001% or less, Ni: 9 to 1
4%, Cr: 22-24%, Mo: 1-2%, Cu:
0.1 to 0.2%, N: 0.1 to 0.2%, the balance Fe and impurities,
The structure of the invention relating to the stainless steel for a telescopic antenna is used as a means for solving the above-mentioned conventional problems.

Next, the reasons for limiting the component composition (% by weight) of the stainless steel for a telescopic antenna according to the present invention will be described.

C: 0.05% or less Since C may deteriorate the corrosion resistance in the heat affected zone due to welding, the content of C is set to 0.05% or less in order to prevent such deterioration of the corrosion resistance.

Si: 1.0% or less Si is an element which acts as a deoxidizing agent during steel melting, but if a large amount of this Si is contained, hot workability is deteriorated. 1% or less.

Mn: 2.0% or less Mn is an element which acts as a deoxidizing agent and a desulfurizing agent during the melting of steel, but if a large amount of this Mn is contained, cold workability is deteriorated. Therefore, it was set to 2.0% or less.

P: 0.05% or less If the content of P is large, the cold workability is deteriorated, so the content is made 0.05% or less.

S: 0.001% or less If the S content increases, the inclusions in the steel increase and the cold workability deteriorates, so the content was made 0.001% or less.

Ni: 9 to 14% Ni is an austenite forming element and is an element useful for improving the corrosion resistance of steel, but in order to prevent the deterioration of the corrosion resistance due to the formation of work-induced martensite during cold working, it is 9 % Or more is necessary. However, even if a large amount is contained, it is not possible to obtain the effect commensurate with the increase in cost, so the content is set to 14% or less.

Cr: 22-24% Cr is a ferrite forming element, but it is an element useful for improving the corrosion resistance of steel, so it is necessary to contain 22% or more. However, if a large amount is contained, a harmful ferrite phase is generated as an antenna. Therefore, the content is set to 24% or less in order to suppress the generation of such a ferrite phase.

Mo: 1-2% Mo is an element useful for improving the corrosion resistance, and it is necessary to contain Mo in an amount of 1% or more in order to delay the rust generation time. However, even if it is contained in a large amount, it is not possible to obtain the effect commensurate with the cost increase, so the content was made 2% or less.

Cu: 0.1 to 0.2% Cu is an element useful for improving the corrosion resistance, and in order to obtain such an effect, it is preferable to contain 0.1% or more. However, if it is contained in a large amount, the weldability deteriorates, so 0.2%
Below.

N: 0.1 to 0.2% N is an austenite forming element and improves the corrosion resistance, so it is preferable to contain N by 0.1% or more. However, if it is too large, the manufacturability of steel is deteriorated, so the content was made 0.2% or less.

[0019]

The stainless steel for a telescopic antenna according to the present invention has the above-described composition and is made of Cr-
Based on Ni-based stainless steel, the action of increasing the content of Ni, which has the effect of preventing the deterioration of corrosion resistance due to the formation of work-induced martensite by cold working, improves corrosion resistance and extends the time of rust generation C, Si, Mn, P that increases the content of Mo, increases the content of Cr that has the effect of preventing the progress of rust, and affects the workability such as roll formability and weldability and corrosion resistance. , S, Cu, N and other trace elements have been adjusted or regulated, it has excellent workability such as roll formability and weldability when manufacturing a telescopic antenna, and the material itself and welded parts are cold. Even if it is subjected to hot working or surface polishing, processing-induced martensite is unlikely to occur, preventing deterioration of corrosion resistance due to the generation of processing-induced martensite and preventing rust from occurring in the material itself or the welded part. Have and excellent corrosion resistance.

[0020]

[Examples] Austenitic stainless steels having the chemical composition shown in Table 1 were used as test materials, and evaluation tests of corrosion resistance and workability were performed.

Among these, the corrosion resistance test was carried out by examining the presence or absence of rust after performing the CASS test for 80 hours, and the corrosion resistance in the general part and the corrosion resistance in the welded part were evaluated separately. The results are shown in the column of corrosion resistance in Table 2.

In the workability test, roll formability and weldability in the actual antenna manufacturing process were examined, and Comparative Example No. The quality was evaluated based on 1 (SUS304). These results are also shown in the processability column of Table 2.

[0023]

[Table 1]

[0024]

[Table 2]

As shown in Tables 1 and 2, Comparative Example No. 3 having a too small Cr content. Steels 1 to 3 are inferior in corrosion resistance in general parts and welded parts,
Comparative Example No. 1 in which the Ni content and the Mo content are too large. Four
In the steel of Comparative Example No. 3, the roll formability was poor and the bead weldability was also poor, and the Cr content was too high and the Ni content was too low. The steel of No. 5 is inferior in roll formability, and has a relatively high Cr content. Comparative Example N
o. Steel No. 7 had poor roll formability.

On the other hand, Invention Example No. Satisfying the compositional composition of stainless steel according to the present invention. 6A, 6B, 6C
Steel has both excellent corrosion resistance and workability, as well as excellent roll formability and weldability when manufacturing an antenna, and excellent corrosion resistance after being used as an antenna. It was confirmed that the occurrence can be prevented for a long period of time, the appearance quality can be maintained to be good, and the elasticity of the antenna can be smoothed for a long period of time.

[0027]

INDUSTRIAL APPLICABILITY The stainless steel for a telescopic antenna according to the present invention has a weight percentage of C: 0.05% or less and Si: 1.0.
% Or less, Mn: 2.0% or less, P: 0.05% or less,
S: 0.001% or less, Ni: 9 to 14%, Cr: 22
-24%, Mo: 1-2%, Cu: 0.1-0.2%,
N: 0.1 to 0.2%, balance Fe and impurities, Ni based on Cr-Ni type stainless steel and having a function of preventing deterioration of corrosion resistance due to formation of work-induced martensite by cold working The content of Mo and increase the content of Mo, which has the effect of extending the rust generation time,
Increasing the content of Cr, which has the effect of preventing the progress of rust, and adding trace elements such as C, Si, Mn, P, S, Cu and N, which affect workability such as roll formability and weldability and corrosion resistance. Since it is adjusted or regulated, it has excellent workability such as roll formability and weldability when manufacturing the telescopic antenna, and even when the material itself or the welded part is subjected to cold working or surface polishing processing. It does not easily generate processing-induced martensite, prevents deterioration of corrosion resistance due to the formation of processing-induced martensite, and is excellent in corrosion resistance that does not easily cause rust in the material itself or the welded part. When used as a material for a telescopic antenna, it is possible to suppress rust generation for a long time even when exposed to a humid environment or salt damage environment.
Since the overall corrosion resistance is improved, it is possible to prevent or reduce damage due to corrosion even in a corrosive environment due to acid rain, volcanic ash, etc., and it is possible to make the elasticity of the antenna smooth for a long time. In addition to being possible, the remarkably excellent effect that the appearance quality can be favorably maintained over a long period of time is brought about.

Claims (1)

[Claims] 1. By weight%, C: 0.05% or less, Si:
1.0% or less, Mn: 2.0% or less, P: 0.05% or less, S: 0.001% or less, Ni: 9 to 14%, Cr:
22-24%, Mo: 1-2%, Cu: 0.1-0.2
%, N: 0.1 to 0.2%, balance Fe and impurities, stainless steel for telescopic antenna.