JPH01116042A - Material for piezoelectric vibrator case - Google Patents

Abstract

PURPOSE:To obtain the above material having high strength and having excellent drawability, resistance weldability, solderability, corrosion resistance and stress corrosion cracking resistance at low cost by specifying the compsn. consisting of Zn, Ni, Mn and Cu. CONSTITUTION:Said material contains, by weight, 3-<20% Zn, 1-15% Ni, 0.001-2.0% Mn and the balance Cu with inevitable impurities. The material is made of inexpensive Cu-Zn-Ni-Mn alloy having high strength, excellent deep drawability and resistance weldability with Fe-42Ni which has been the conventional advantages of German silver and having more excellent solderability, corrosion resistance and stress corrosion cracking resistance than those of German silver.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a material for a case of a piezoelectric (crystal) resonator, and more specifically, a material for a case of a sealed piezoelectric resonator that has excellent drawing workability and corrosion resistance. Regarding.

[Conventional technology]

Piezoelectric elements are widely used in oscillators, resonators, filters, phase shifters, etc., and technical development of crystal resonators in particular is actively progressing as demand for electronic devices increases.

Piezoelectric materials include quartz crystal and lead zirconate titanate ceramic, but when appropriate electrodes are placed on these materials and an alternating current electric field is applied, stress at the same frequency as that of the piezoelectric material is generated due to the piezoelectric effect.
Alternatively, it causes strain, and when the frequency of the electric field matches the natural frequency of the material's elastic vibration, it resonates and causes strong vibration. A piezoelectric element takes advantage of this phenomenon, and consists of electrodes placed on a piezoelectric substrate, mechanically supported by support wires, and enclosed in a case.

Conventionally, such sealing type pressure 1! As a material for a (crystal) resonator case, nickel silver such as 64 Cu-18N i -Z n has been mainly used. This kind of material is
Needless to say, it must be excellent in many properties such as strength, drawability, corrosion resistance, stress corrosion cracking resistance, plating performance, and solderability.
-29Ni-17C.

Alternatively, it is necessary to have excellent resistance weldability with Fe-42Ni.

Furthermore, piezoelectric vibrators are electronic components and cannot be treated as an exception, and even the small components that make up the piezoelectric vibrators have been reconsidered from various aspects.

The nickel silver used as the material for this piezoelectric vibrator case has excellent strength, drawing workability, and resistance weldability with Fe-42Ni, but it also has poor solderability, corrosion resistance, stress corrosion cracking resistance, and plating properties. There is a problem with N.
It is used with plating such as i-plating, and
Generally, after horizontal continuous casting, nickel silver is repeatedly cold rolled and annealed to make a plate material, which makes the process very complicated and expensive.

[Problem that the invention seeks to solve]

The present invention is based on the advantage of nickel silver, which has been conventionally used as a material for the piezoelectric vibrator case.

An inexpensive Cu that has high strength, excellent drawing workability, and excellent resistance weldability with Fe-42Ni, and also has better solderability, corrosion resistance, and stress corrosion cracking resistance than nickel silver.
The present invention provides a piezoelectric vibrator case material made of -Zn-Ni-Mn alloy.

[Means for solving problems]

The material for the piezoelectric vibrator case according to the present invention is as follows.

Contains 3 wt% or more and less than 20 wt% Zn, 1 to 15 wt% Ni, 0.001 to 2.0 wt% Mn, and the balance is C.
The present invention relates to a material for a piezoelectric vibrator case characterized by comprising u and inevitable impurities.

The reasons for limiting the components and component ratios of the piezoelectric vibrator case material according to the present invention will be explained.

Cu and Zn are the basic components of the material of the present invention, and the processability 1
Improves mechanical properties and deep drawing workability.

The reason why the Zn content is set to 3 wt% or more and less than 20 wt% is that if the Zn content is less than 3 wt%, it will not be effective in improving the strength, and if it is 20 wt% or more, the soldering properties will deteriorate.

Preferably, Zn content of 10 wt% or more provides higher strength and lower cost.

Ni is an element that improves strength, corrosion resistance, and stress corrosion cracking resistance, and the reason why the Ni content is set to 1 to 15 wt% is as follows.
When the Ni content is less than 1 wt%, there is almost no effect;
If it exceeds 5wt%, workability and soldering properties will deteriorate.
This is because the price also increases.

Mn is an element that improves hot workability, deep drawability, and strength. M
The n content is 0.001 to 2. The reason for OW and % is M
This is because if the n content is less than 0.001 wt%, there is almost no effect, and if it exceeds 2.0 wt%, the soldering properties deteriorate.

〔Example〕

Next, the present invention will be explained in detail.

An alloy having the composition shown in Table 1 was melted and subjected to hot rolling, appropriate cold rolling, and annealing to produce a plate with a thickness of 0.25 m and a crystal grain size of about 10 to 15 μm.

For these alloys, tensile strength, elongation, critical drawing ratio,
Soldering properties, Ni plating properties, corrosion resistance, and stress corrosion cracking resistance were investigated. The results are also listed in Table 1.

Tensile strength and elongation were evaluated using a JISS No. tensile test piece and a Tensilon type tensile tester.

The critical drawing ratio was determined by performing a deep drawing test using a 33 mφ punch.

Soldering temperature is 230℃, 6S n / 4P b
In a solder bath, use rosin-methanol as a flux and polish the surface with #1200 emery paper.
A wet test piece (0.25xlOx50) was immersed for 5 seconds to investigate the wetting state of the solder.

Ni plating property was determined by Watt bath (nickel sulfate 240g/f).
After Ni plating was performed to a thickness of 1.5 μm using 40 g/Q of nickel chloride and 35 g/Q of boric acid, 180′ close bending was performed once to examine the adhesion of the plating at the bent portion.

Corrosion resistance is 40℃, humidity tw containing 25ppm SO□
A test piece (0.25 x 40 x 60
) was exposed for 196 hours and the appearance was observed.

Stress corrosion cracking resistance was determined in accordance with JIS C8306 for each material before and after Ni plating (1.5 μm) formed into a cup with a blank diameter of 66 m and a punch diameter of 33 m1 in a desiccator with an internal volume of 10Q containing test liquid IQ (20 ±2
℃), and after 100,200,500 hours, it was taken out from the desiccator and the presence or absence of cracks was confirmed. In addition, the test liquid is about 700 g of special grade ammonium chloride.
mQ of distilled water, add a solution of 50 to 70 g of special grade sodium hydroxide dissolved in about 250 mI of distilled water, and when the hydrogen ion concentration (pH) reaches 10, the total amount becomes about IQ. Distilled water was added to adjust.

As is clear from Table 1, compared to the comparative alloys, the alloy of the present invention has better strength, solderability, corrosion resistance, deep drawability,
It also has excellent stress corrosion cracking resistance.

Moreover, it has the characteristic that it can be manufactured at a significantly lower cost than other materials such as nickel silver.

〔Effect of the invention〕

As detailed above, the alloy of the present invention has sufficient strength, deep drawability, good stress corrosion cracking resistance, and is inexpensive, so it is optimal as a material for a piezoelectric vibrator case.

Claims (1)

[Claims] (1) Zn of 3wt% or more and less than 20wt%, 1 to 15w
Containing t% Ni, 0.001 to 2.0wt% Mn,
A material for a piezoelectric vibrator case, characterized in that the remainder is Cu and unavoidable impurities.