CN112577818B - A tensile test fixture for flake solid propellants - Google Patents

Abstract

The present invention proposes a sheet-like solid propellant tensile test fixture, which includes three parts: a tensile device connector, a sample fixing part and a lock; the tensile device connector consists of a cylindrical base, a connecting rod and an upper part from bottom to top. The upper half cylinder is fixed on the top of the connecting rod by welding, etc., and the rotation axis of the upper half cylinder deviates from the axis of the connecting rod; the sample fixture is composed of a fixed half cylinder and a cylinder perpendicular to the rectangular surface of the fixed half cylinder. The radius of the semi-cylindrical is equal to the radius of the upper semi-cylindrical of the stretching equipment connector; the cylinder perpendicular to the rectangular surface of the fixed semi-cylindrical matches the round hole of the upper semi-cylindrical rectangular surface of the stretching device connector. Through the fitting of the upper semi-cylindrical of the sample fixing part and the connecting part of the tensile equipment, the sheet solid propellant can be clamped between the rectangular surfaces of the two, and the sample fixing part and the connecting part of the tensile equipment can be locked by a lock fasten.

Description

A tensile test fixture for flake solid propellants

technical field

The invention relates to a sheet-shaped solid propellant tensile test fixture, which belongs to the technical field of solid propellant testing and is used for the research on the mechanical properties of solid propellant.

Background technique

The continuous improvement of the diverse demands of militarization tasks requires propellants to have better high and low temperature mechanical properties. In order to conduct in-depth research on the damage mechanism of propellants, many testing methods for microscopic damage and evolution of propellants have been developed. Therefore, it is also necessary to design a fixture for stretching thin sheet samples to ensure the accuracy of the test. Chinese patent 200320121616.1 proposes "a tensile test fixture", which includes a plate-shaped main body, a recessed area, a constriction and a cover plate. The two ends of the sample are respectively embedded in the recessed area, and the front and back of the sample are equipped with thick elastic gaskets to ensure the centering, and then the sample is pressed tightly with the cover plate, and the screws are tightened on the side. After the sample is installed, use The pins fix the through hole with the universal connection shaft of the testing machine, and finally place it in a closed low-temperature tensile test container for measurement. The in-situ stretching device disclosed in this document has the following defects: 1. The fixture is not easy to install, which is destructive to the sample; 2. The sample is fixed through the groove, which has restrictions on the thickness of the sample, and cannot be pulled by the sheet propellant. 3. The structure of the fixture is complicated.

Contents of the invention

In order to solve the problems existing in the prior art, the present invention proposes a sheet-shaped solid propellant tensile test fixture, which includes three parts: a tensile device connector, a sample fixture and a lock.

The connecting part of the stretching equipment is composed of a cylindrical base, a connecting rod and an upper half cylinder.

A plurality of connection threaded holes are opened on the bottom surface of the cylindrical base for fixed connection with the external tension sensor. The connecting rod is coaxially fixed on the top surface of the cylindrical base, and the cylindrical radius of the connecting rod is one-eighth of the radius of the cylindrical base. The radius of the upper half cylinder is a quarter of the radius of the base of the cylinder, and the upper half cylinder is fixed on the top of the connecting rod by means of welding, etc., and the rotation axis of the upper half cylinder deviates from the axis of the connecting rod, and the deviation is 1/6 of the radius of the connecting rod cylinder one. A circular hole with a radius of one-eighth of the axial length of the semi-cylindrical is opened at a position three quarters away from the top of the upper semi-cylindrical, and the circular hole is perpendicular to the rectangular surface of the upper semi-cylindrical.

The sample fixture is composed of a fixed half cylinder and a cylinder perpendicular to the rectangular surface of the fixed half cylinder, the radius of the fixed half cylinder is equal to the radius of the upper half cylinder of the tensioning equipment connection, and the axial length is equal to the upper half of the tension equipment connection. The axial length of the cylinder; the cylinder perpendicular to the rectangular surface of the fixed semi-cylindrical is at a position three-quarters away from the top of the fixed semi-cylindrical, and matches the circular hole on the rectangular surface of the upper semi-cylindrical surface of the stretching equipment connector.

The lock is composed of an elastic circular tube with a notch and a fixed piece at the position of the notch; the inner diameter of the elastic circular tube is equal to the radius of the fixed semi-cylinder, and the axial length of the elastic circular tube is equal to the axial length of the fixed semi-cylindrical. The lock can be set on the outside of the combination of the sample fixture and the upper half cylinder of the tensioning equipment connection, and by installing bolts in the fastening holes on the fixing piece, the sample fixture and the upper half of the tension equipment connection are realized. Cylindrical fastening.

Through the fitting of the upper semi-cylindrical part of the sample fixing part and the connecting part of the tensile equipment, the sheet solid propellant can be clamped between the rectangular surfaces of the two, and the sample fixing part and the connecting part of the tensile equipment can be locked by a lock fasten.

Beneficial effect

(1) The present invention fixes the sample through locks, which can ensure that the sample does not deviate, and the large fixing surface can effectively prevent the sample from slipping.

(2) The connecting part of the tensioning equipment and the fixing part of the sample of the present invention adopt shaft hole cooperation, which is convenient for installation and unloading.

(3) The sample fixing part of the present invention can control the distance from the connecting part of the stretching equipment according to the thickness requirement of the sample.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and understandable from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is the main sectional view of the solid propellant tensile test fixture of the present invention.

Fig. 2 is a top view of the connecting part of the stretching equipment in Fig. 1 .

Fig. 3 is a cross-sectional view along the A-A direction of the stretching equipment connector in Fig. 2 .

Fig. 4 is a sectional view along the B-B direction of the stretching equipment connecting part in Fig. 2 .

Fig. 5 is a cross-sectional view of the connecting part C-C of the stretching equipment in Fig. 4 .

FIG. 6 is a perspective perspective view of the connecting part of the stretching equipment in FIG. 1 .

Fig. 7 is a front sectional view of the sample holder in Fig. 1 .

Fig. 8 is a left side view of the sample holder in Fig. 1 .

FIG. 9 is a top view of the sample holder in FIG. 1 .

FIG. 10 is a perspective view of the sample holder of FIG. 1. FIG.

Fig. 11 is a main sectional view of the buckle in Fig. 1 .

Fig. 12 is a sectional view along the A-A direction of the latch in Fig. 11 .

In the figure, 1-tensile equipment connection piece, 2-sample fixing piece, 3-lock buckle, 4-sample.

Detailed ways

Embodiments of the present invention are described in detail below, and the embodiments are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

As shown in FIG. 1 and FIG. 2 , the sheet-shaped solid propellant tensile test fixture in this embodiment includes three parts: a tensile device connection part 1 , a sample fixing part 2 and a lock 3 .

As shown in Figures 3 to 6, the connecting piece of the stretching equipment is composed of a cylindrical base, a connecting rod and an upper half cylinder.

Four connection threaded holes are opened on the bottom surface of the cylindrical base for fixed connection with the external tension sensor. The connecting rod is coaxially fixed on the top surface of the cylindrical base, and the cylindrical radius of the connecting rod is one-eighth of the radius of the cylindrical base. The radius of the upper half cylinder is a quarter of the radius of the base of the cylinder, and the upper half cylinder is fixed on the top of the connecting rod by welding, and the rotation axis of the upper half cylinder deviates from the axis of the connecting rod, and the deviation is one-sixth of the radius of the connecting rod cylinder . A circular hole with a radius of one-eighth of the axial length of the semi-cylindrical is opened at a position three quarters away from the top of the upper semi-cylindrical, and the circular hole is perpendicular to the rectangular surface of the upper semi-cylindrical.

As shown in Figures 7 to 10, the sample fixture is composed of a fixed half cylinder and a cylinder perpendicular to the rectangular surface of the fixed half cylinder. The radius of the fixed half cylinder is equal to the radius of the upper half cylinder of the tensioning equipment connector. The length is equal to the axial length of the upper half cylinder of the tensioning equipment connection; the cylinder perpendicular to the rectangular surface of the fixed half cylinder is at a position three-quarters away from the top of the fixed half cylinder, and the distance between the upper half cylinder and the rectangular surface of the tensioning equipment connection round holes to match.

As shown in Figure 11 and Figure 12, the lock is composed of an elastic circular tube with a notch and a fixed piece at the position of the notch; the inner diameter of the elastic circular tube is equal to the radius of the fixed half cylinder, and the axial length of the elastic circular tube is equal to the fixed half cylinder. The axial length of the cylinder, the locking buckle can be set outside the combination of the sample fixing part and the upper half cylinder of the tensile equipment connection part, and by installing bolts in the fastening holes on the fixing piece, the sample fixing part and The upper semi-cylindrical fastening of the connecting piece of the stretching equipment.

The solid propellant formulation parameters of the present embodiment:

The mass percentages of each component are: 17% of aluminum powder, 13% of binder system, and 70% of ammonium perchlorate.

Through the fitting of the upper semi-cylindrical part of the sample fixing part and the connecting part of the tensile equipment, the sheet solid propellant can be clamped between the rectangular surfaces of the two, and the sample fixing part and the connecting part of the tensile equipment can be locked by a lock fasten.

Based on the above solid propellant tensile test fixture, this embodiment conducts a propellant stress-strain curve test at room temperature. The experimental results show that the sheet-like solid propellant tensile test fixture in this embodiment can be well applied to the tensile mechanical test at room temperature, the results are accurate and reliable, and the fixture itself has no influence on the experimental results, and after multiple tests of the same kind The results of sample repeated experiments show that the repeatability of the data is good, which can meet the needs of mesoscopic damage observation.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be construed as limitations to the present invention. Variations, modifications, substitutions, and modifications to the above-described embodiments are possible within the scope of the present invention.

Claims (5)

1. The utility model provides a slice solid propellant tensile test anchor clamps which characterized in that: the device consists of a stretching equipment connecting piece, a sample fixing piece and a lock catch;

the stretching equipment connecting piece consists of a cylindrical base, a connecting rod and an upper semi-cylinder;

the bottom surface of the cylindrical base is provided with a plurality of connecting threaded holes for fixedly connecting with an external tension sensor; the connecting rod is coaxially fixed on the top surface of the cylindrical base, the upper semi-cylinder is fixed on the top end of the connecting rod, and the rotation axis of the upper semi-cylinder deviates from the axis of the connecting rod; round holes perpendicular to the rectangular surface are formed in the rectangular surface of the upper semi-cylinder;

the sample fixing piece consists of a fixing semi-cylinder and a cylinder perpendicular to the rectangular surface of the fixing semi-cylinder, the radius of the fixing semi-cylinder is equal to that of the upper semi-cylinder of the stretching equipment connecting piece, and the axial length of the fixing semi-cylinder is equal to that of the upper semi-cylinder of the stretching equipment connecting piece; the cylindrical position and the size of the cylindrical surface vertical to the fixed semi-cylindrical rectangular surface are matched with the round hole of the semi-cylindrical rectangular surface at the upper part of the stretching equipment connecting piece;

the lock catch consists of an elastic round tube with a notch and a fixing piece at the position of the notch; the inner diameter of the elastic round tube is equal to the radius of the fixed semi-cylinder, and the axial length of the elastic round tube is equal to the axial length of the fixed semi-cylinder;

the sample fixing piece and the upper semi-cylinder of the stretching equipment connecting piece are matched, so that the flaky solid propellant can be clamped between rectangular surfaces of the sample fixing piece and the upper semi-cylinder of the stretching equipment connecting piece, the flaky solid propellant is sleeved outside the assembly of the sample fixing piece and the upper semi-cylinder of the stretching equipment connecting piece through the lock buckle, bolts are installed in the fastening holes on the fixing piece, the sample fixing piece and the upper semi-cylinder of the stretching equipment connecting piece are fastened, and the flaky solid propellant is clamped tightly.

2. The sheet-like solid propellant tensile test fixture of claim 1, wherein: the radius of the cylinder of the connecting rod is one eighth of the radius of the cylinder base, and the radius of the upper semi-cylinder is one fourth of the radius of the cylinder base.

3. The sheet-like solid propellant tensile test fixture of claim 1, wherein: the upper semi-cylinder is fixed at the top end of the connecting rod in a welding mode.

4. The sheet-like solid propellant tensile test fixture of claim 1, wherein: the upper semi-cylindrical rotation axis is offset from the connecting rod axis by one sixth of the radius of the connecting rod cylinder.

5. The sheet-like solid propellant tensile test fixture of claim 1, wherein: a round hole with a radius of one eighth of the axial length of the upper half cylinder is formed on the rectangular surface of the upper half cylinder at a position which is three quarters away from the top of the rectangular surface of the upper half cylinder.

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