JP2016102254A - Phosphor bronze alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for enhancing heat insulating property by validating heat conductivity of phosphor bronze and propose applications to building materials such as roof materials and wall materials requiring heat insulating property.SOLUTION: Heat insulating property with heat conductivity of 200 (W/m k) can be achieved by constituting a phosphor bronze alloy by tin of 11 wt.% or less (excluding 0), phosphor of 0.15 wt.% or more and the balance copper with inevitable impurities.SELECTED DRAWING: None

Description

  The present invention relates to a phosphor bronze alloy having low thermal conductivity, that is, high heat insulation.

  There is a trace that iron or gold derived from pig iron was used before copper, but copper has been used for various purposes since prehistoric times because it is produced as natural copper and easy to process. . In Japan as well, a considerable amount of copper has been used for a long time, as seen in excavations such as bronze caskets, bronze mirrors and bronze bars from the ruins of various places.

  In Japan, the oldest example of copper being used as a roofing material is the Sadaiji Temple in Nara, which was erected during the Tenpyo period. In the Edo period, as copper processing technology advances, the amount used for roofing materials increases, and Nikko Toshogu is a typical example.

  And most copper plates used as a roofing material are phosphorus deoxidized copper. However, phosphorous deoxidized copper has a high thermal conductivity, so it has a low thermal insulation and has a surface unsuitable as a roofing material.

  On the other hand, phosphor bronze is an alloy containing tin, is excellent in mechanical strength and conductivity, and is excellent in workability. Therefore, phosphor bronze is used in electronic parts and various electric products. Since it is excellent in processability, it can be easily processed into a shape suitable for the application. By enhancing this feature and the heat insulation, application development different from the conventional one can be expected.

  From this point of view, that is, from the viewpoint of the characteristic of thermal conductivity, for example, Patent Document 1 discloses a cylindrical container having a longitudinal direction as a direction in which heat is to be transferred, and a container. There is disclosed a technology for forming a part of a wick functional material with phosphor bronze, which is a heat pipe having a wick functional material disposed in a container as a constituent element. However, what is disclosed here is a heat pipe that applies the high thermal conductivity of phosphor bronze, and no mention is made of heat insulation.

  In addition to the above, Patent Literature 2 to Patent Literature 4 disclose phosphor bronze applied technologies, both of which utilize the high thermal conductivity of phosphor bronze, and have heat insulation properties. At present, it must be said that there is virtually no technology that expands the application by improving the above.

  JP 2010-216712 A   JP 2006-1000048 A   JP 09-252174 A   JP 05-004874 A

  Therefore, it is an object of the present invention to verify the thermal conductivity of phosphor bronze, provide a method for improving heat insulation, and propose use for building materials such as roofing materials and wall materials that require heat insulation. is there.

  The present invention has been made as a result of examining the relationship between the content of tin and phosphorus in phosphor bronze and the thermal conductivity in view of the above problems, and finding that the heat insulation can be improved to a required value. .

  That is, the present invention includes 11% by weight or less (excluding 0) of tin and 0.15% by weight or more of phosphorus, with the balance being copper and inevitable impurities, and a thermal conductivity of 200 (W / m · k) or less, a phosphor bronze alloy.

The present inventors have examined the relationship between phosphorus content and heat insulating properties, in other words, thermal conductivity, in a phosphor bronze alloy by a thermal conductivity test. As a result, the tin content is 11 wt% or less, phosphorus It was found that the phosphor bronze alloy exhibits higher heat insulation than phosphorous deoxidized copper in the region of the content of 0.15% by weight or more.

  In general, heat conduction in metals contributes to energy transfer as vibration of the crystal lattice and energy transfer based on free electrons, but by increasing the phosphorus content in phosphor blue steel, both contributions are reduced. It is understood that the thermal conductivity is lowered and the heat insulation is improved.

  The figure which shows the relationship between the phosphorus content rate and thermal conductivity in the phosphor bronze alloy of this invention.

  Next, an embodiment of the present invention will be described by explaining the phosphorus content and the heat insulating property (thermal conductivity) of the phosphor bronze alloy. Here, a sample for measuring thermal conductivity was prepared so that the tin content and the phosphorus content shown in Table 1 were obtained. The thermal conductivity was measured at room temperature by the laser flash method.

  The results are also shown in Table 1 and FIG. The phosphorus content in ordinary phosphor blue steel is around 0.1 wt%. From these results, however, the increase in the phosphorus content greatly reduces the thermal conductivity, and significantly improves the heat insulation. It is apparent that the thermal conductivity becomes 200 (W / m · k) or less by setting the phosphorus content to 0.15% or more.

  As described above, according to the present invention, a phosphor bronze alloy having excellent heat insulation can be provided. The present invention is not limited to the above-described embodiment, and does not depart from the gist of the present invention, including various modifications and corrections that can be conceived by those having ordinary knowledge in the field of the present invention. Of course, even if there is a design change in the range, it is included in the present invention.

Claims (1)

  It contains 11 wt% or less (excluding 0) tin and 0.15 wt% or more phosphorus, the balance is made of copper and inevitable impurities, and the thermal conductivity is 200 (W / m · k) or less. A phosphor bronze alloy characterized by being.

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