TWI546393B - Niobium brass - Google Patents

Description

Brass

This invention relates to a brass, and more particularly to a brass.

Brass refers to copper-zinc alloys with copper as the main component; other elements that can improve the properties of brass itself, such as lead, tin, aluminum, etc., can be added as needed. Although brass has high cutting properties compared to copper or other copper alloys, it has poor corrosion resistance.

In the past, the addition of lead to brass has increased the machinability of brass, and lead brass has been widely used in over-water workpieces (such as water pipes) in the drinking water industry. However, most of the water-passing workpieces are used as pipelines for drinking water containing chlorine, and they are often used in high-temperature environments. These environments are mostly rich in other charged particles, and the water-soluble workpieces are yellowed after long-term immersion. Copper will be dezinced and corroded, resulting in perforation of the workpiece, resulting in shortened service life, and lead brass will also precipitate toxic lead into drinking water, thus endangering human health. Although there are currently studies using bismuth instead of lead in brass, since bismuth and lead all have the same low melting point characteristics, squeezing brass is as easy to produce as high temperature due to high temperature. burst.

Therefore, to find a higher melting point, can prevent the dezincification corrosion of brass, can improve the machinability of brass and is non-toxic to the human body to replace lead plus Into the brass, has become the goal of current research.

In view of the problems caused by the use of the aforementioned lead brass or bismuth brass, the inventors of the present invention first thought of using a crucible having a high melting point and being non-toxic to the human body instead of adding lead or antimony to the brass.

Therefore, the first object of the present invention is to provide a bismuth brass which can prevent dezincification corrosion, has high machinability, is not easily broken in a high temperature environment, and does not precipitate toxic elements.

Thus, the bismuth brass of the present invention contains 0.05 to 0.6 parts by weight of bismuth and 99.4 to 99.95 parts by weight of brass, based on 100 parts by weight of the total.

Accordingly, a second object of the present invention is to provide a method of preventing dezincification corrosion of brass.

The method of the present invention for preventing dezincification of brass includes a step of adding bismuth to the brass.

The effect of the invention is to add a high melting point and non-toxic bismuth to the brass to form a bismuth brass alloy, thereby preventing dezincification corrosion of the brass, and at the same time improving the machinability of the brass, so that the brass is not easily cracked in a high temperature environment. And will not precipitate toxic elements.

The contents of the present invention will be described in detail below: Preferably, the niobium content ranges from 0.05 to 0.4 parts by weight based on 100 parts by weight of the total weight of the niobium brass. More preferably, the cerium content is 0.077 parts by weight.

The brass of the invention can be adjusted in brass according to the requirements of subsequent applications. The copper and zinc contents are preferably, in terms of 10% by weight based on the total weight of the brass, the brass comprises 40 to 80% by weight of copper, and 20 to 60% by weight of zinc. More preferably, the brass comprises 50 to 70% by weight of copper and 30 to 50% by weight of zinc. Still more preferably, the brass comprises 55 to 65 wt% copper and 35 to 45 wt% zinc.

The method for preventing dezincification corrosion of brass according to the present invention can adjust the content of cerium added to the brass according to the subsequent application requirements. Preferably, 0.05 to 0.6 parts by weight of cerium is added to the brass of 99.4 to 99.95 parts by weight. More preferably, 0.05 to 0.4 parts by weight of hydrazine is added. Still more preferably, 0.077 parts by weight of hydrazine is added.

The preparation method of the bismuth brass of the invention is to sequentially add copper block, zinc block and bismuth powder in a high-frequency furnace, and smelt at a high temperature, and finally hold the temperature at 1100~1300 ° C for 5 minutes, then pour into 80-85 ° C. The mold was then taken out of the mold and cooled to room temperature to produce a bismuth brass alloy.

The present invention will be further illustrated by the following examples, but it should be understood that this embodiment is intended to be illustrative only and not to be construed as limiting.

Source of chemicals

Copper block: Landon Metal Industrial Co.,Ltd.

Zinc block: Lai-I Metal Industrial Co.,Ltd.

铌 powder: Weiss Enterprise Co., Ltd.

Comparative example 1

Preparation of brass alloy: In a high-frequency furnace, 171g copper block and 114.6g zinc block were sequentially added and smelted at high temperature. Finally, after holding at 1100~1300°C for 5 minutes, pour the mold into 80~85°C. Then, the casting in the mold was taken out and cooled to room temperature to obtain a brass alloy.

Examples 1 to 5 and Comparative Example 2

Preparation of bismuth brass alloy: Examples 1 to 5 and Comparative Example 2 were sequentially added to a copper block, a zinc block, and a niobium powder (Nb) in a high-frequency furnace according to the amounts shown in Table 1 below, at a high temperature. After smelting, finally holding the temperature at 1100~1300 °C for 5 minutes, pour the mold into 80~85 °C, then take out the castings in the mold and cool to room temperature to obtain the bismuth brass alloy.

test analysis

1. Component content ratio analysis: The brass alloy of Comparative Example 1 and Comparative Example 2 and the bismuth brass alloys of Examples 1 to 5 were respectively cut into a test piece, and then inductively coupled plasma mass spectrometer (ICP- MS) Analysis of the content ratio of each test piece component is shown in Table 2 below.

According to Table 2, the bismuth brass alloys obtained in Comparative Example 2 and Examples 1 to 5 had a ruthenium content ratio of 0.029%, 0.051%, 0.062%, 0.077%, and 0.419, respectively, based on 100% of total weight. %, 0.597%. On the other hand, the brass alloy prepared in Comparative Example 1 was not detected to contain antimony.

2. Dezincification test: The brass alloy of Comparative Example 1 and Comparative Example 2 and the bismuth brass alloy of Examples 1 to 5 were respectively cut into a test piece, and the degree of dezincification corrosion was measured by the AS2345 Australian Standard Test. Test, the results are shown in Table 3.

3. Machinability test: The brass alloy of Comparative Example 1 and Comparative Example 2 and the bismuth brass alloys of Examples 1 to 5 were respectively cut into a test piece, and the cutting performance test was performed. The results are shown in Table 3. Show.

When the depth of the dezincification layer is higher, the lower the ability of the brass to prevent dezincification corrosion, the data of Table 3 shows that the brass containing bismuth (Examples 1 to 5) is compared with the brass without bismuth (Examples 1-5) In Comparative Example 1), the depth of the dezincification layer was greatly lowered, and it was shown that the ability to prevent dezincification corrosion was increased when bismuth was formed in the brass to form a bismuth brass alloy. Among them, Table 3 further has a minimum dezincification depth of brass containing 0.077% bismuth (Example 3), and its dezincification resistance is improved by 95% compared with brass without bismuth (Comparative Example 1), thus containing 0.077% bismuth brass has the best resistance to dezincification.

The lower the cutting length, the better the machinability of the brass. Therefore, it can be seen from the data in Table 3 that the brass containing bismuth (Examples 1 to 5) is compared with the brass without bismuth (Comparative Example 1). The cutting length is greatly reduced, which shows that if brass is added to the bismuth to form a bismuth brass alloy, the machinability of the brass can be greatly improved.

According to the results of Comparative Example 2, although the anti-dezincification corrosion resistance was obtained in accordance with the demand when the niobium content was 0.029%, the machinability did not meet the demand.

In summary, the bismuth brass of the present invention is a bismuth brass which is added with a high melting point and is non-toxic to form a bismuth brass alloy, thereby preventing dezincification corrosion of the brass, and at the same time improving the machinability of the brass and making the yellow Copper does not easily burst in a high temperature environment and does not precipitate toxic elements, so the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

Claims (9)

A bismuth brass comprising 0.05 to 0.6 parts by weight of bismuth and 99.4 to 99.95 parts by weight of brass, based on 100 parts by weight of the total. The bismuth brass according to claim 1, wherein the cerium content is in the range of 0.05 to 0.4 parts by weight. The bismuth brass according to claim 2, wherein the cerium content is 0.077 parts by weight. The bismuth brass according to claim 1, wherein the brass comprises 40 to 80% by weight of copper, and 20 to 60% by weight of zinc. The bismuth brass according to claim 4, wherein the brass comprises 50 to 70% by weight of copper, and 30 to 50% by weight of zinc. The bismuth brass according to claim 5, wherein the brass comprises 55 to 65 wt% of copper, and 35 to 45 wt% of zinc. A method for preventing dezincification of brass, comprising the step of adding cerium to brass, wherein the step is to add 0.05 to 0.6 parts by weight of cerium to 99.4 to 99.95 parts by weight of brass. The method of claim 7, wherein the hydrazine is used in an amount of 0.05 to 0.4 parts by weight. The method of claim 8, wherein the hydrazine is used in an amount of 0.077 parts by weight.