JPS60114560A - Manufacture of thruster - Google Patents

Abstract

PURPOSE:To obtain a lightweight uncooled thruster by spraying a high m.p. metal with high heat conductivity on a mandrel to form a film and by removing the mandrel chemically and/or physically. CONSTITUTION:A metal such as Mo, Nb or Ni is sprayed on a mandrel 1 of Al or the like from a spray gun 2 to a necessary thickness while rotating the mandrel 1 in the direction of an arrow. The mandrel 1 having the sprayed metal is immersed in an aqueous NaOH soln. having 10-20% concn. to dissolve only the mandrel 1. The resulting formed metallic body (metallic film) has a high m.p. and high heat conductivity and can be used as a thruster as it is. The thruster is that of an apogee kick motor for an artificial satellite. It may be composed of the combustion chamber and nozzle skirt of a rocket engine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a novel thruster (a device that generates propulsive force such as a jet engine, a rocket engine, etc.).
In other words, it refers to a propulsion device, and in the present invention, combustion? (The following nozzle skirt tractor, injector for injecting fuel and oxidizing agent, etc. are collectively called a thruster) manufacturing method.

An example of a low-thrust gas jet thruster used for an artificial 1'Xf star is shown in Fig. It is made by machining from metal Ih such as stainless steel.When this thruster is used, the temperature of the combustion chamber wall reaches tens of hundreds of degrees (Celsius), so it takes time to cool the thruster.In the example shown in Figure 1, the combustion chamber and Cooling piping is installed on the outer wall of the nozzle part, and a cooling medium is flowed into the piping to cool the thruster.

Not only the above-mentioned thrusters but also general aerospace equipment is required to be lightweight. However, conventional thrusters require a cooling device, which is disadvantageous in system design due to the weight burden caused by the cooling device.

The present invention was made in order to manufacture a lightweight, non-cooled thruster for use in low-thrust gas jet thrusters for artificial satellites, etc.

That is, the present invention relates to a method for manufacturing a thruster, which comprises spraying a clay VC sieve melting point/high thermal conductivity metal onto a mandrel to form a coating, and then chemically and/or physically removing the mandrel after FC. It is something.

The non-inventive method is to produce Ao from 44 metals (not by machining, but by thermal spraying) like conventional products.
It is an unprecedented idea to form a structure with a gold striped layer made of materials such as Nb, which has a high melting point and excellent thermal conductivity, and has the advantage of not requiring a cooling device. It is something that you have.

The present invention is based on the artificial 11-7 star Abojiki Tsukumoke Rusk, the artificial 1jtj star low-thrust Kasursk, the rocket engine combustion chamber and nozzle skirt, and the aviation equipment that uses the 4M construction and binding of the rocket engine combustion chamber and nozzle skirt. It can be applied to space equipment, etc.

21st! gl t:t, step 11 of an example of a laughing implementation of an unknown method! Figures ``I'' and ``J'' show an example of manufacturing the combustion chamber and nozzle skirt of a low-thrust gas jet thruster for a hepatic star by plasma spraying.

First, make mandrel 1 as shown in Figure 2.

- Aluminum was used for the mandrel in this example because it was eluted with NaOH in the final layer, but it was necessary to remove the mandrel without having a negative effect on the sprayed metal.
10,000 F, example ri Mg, g4. Pb alloy, Cu may be used, and the removal force method is not limited to NaOH but HN 03
eHot, HF, and HNO3+HF mixed liquids can also be used, and even a single physical one is fine. The outer shape and dimensions of this mandrel 1 are made to match the inner shape and dimensions of the finally required metal molded body. Note that FIG. 2 (1) CB) is a sectional view taken along line AA' in FIG. 2 (1) (-).

Next, as shown in FIG. 2 (2), while rotating the mandrel 1 in the direction of the arrow, the remaining end (for example, Mo
, Nb, Ni, Ta, W, etc. (in this example, molybdenum, niobium or nickel) is thermally sprayed to the required size 1. Figure 2 (2) (B) shows the state after thermal spraying.
FIG. 2 is a sectional view taken along line A-A in FIG.

Thereafter, as shown in FIG. 2(3), it is immersed in an aqueous NaOH solution (10% to 20%) to elute only the mandrel.

Figure 2 (4) shows the final form consisting only of the metal molded body, and Figure 2 (4) (B) is A - of Figure 2 (4) (A).
This is a side view of A'1.

The melting points of the five metal molded products obtained as above are as follows:
Although it has high thermal conductivity and can be used as a thruster, the cooling piping shown in FIG. 1 is uncomfortable.

In addition, in order to confirm the effect of the metal molded body (thruster) in ii2 above, a different type of two-point blast type injector was added to the thruster, and monomethylhydrazine was used as the propellant and N as the oxidizing agent.
When we conducted an experiment using 2O4, the combustion nozzle temperature was approximately 2500'C, the nozzle inner wall temperature was approximately 1500°C,
The temperature of the outer wall of the nozzle portion was about 1000°C.

[Brief explanation of drawings]

Figure 1 (A), (Diagram showing a conventional I3J thruster,
FIGS. 2(1) to 2(4) are diagrams showing an embodiment of the method of the present invention in order of steps. Sub-Agent [I (Meifuku Agent Ryo Hagiwara - Figure 1 Figure 2 Figure 2 Continued from Page 1 0 Inventor Yo Kakuma 2nd Division Inside Daikuoki Seisakusho, Minato-ku, Nagoya City)

Claims (1)

[Claims] A method for producing a thruster, which comprises forming a film on a mandrel by thermally spraying a metal with high melting point and high thermal conductivity, and then chemically and/or physically removing the mandrel.