JPS6125039A - Device for testing hardness - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention includes a hard indenter that can come into contact with the monthly sample and first contacts the monthly sample at the contact point, and applies a load to the indenter that is in contact with the monthly sample. The present invention relates to a device for testing the hardness of material samples made of metals, synthetic resins, elastomers, etc., with which the indentation of an indenter into the material sample can be measured under a test force of

E. Prior art and its problems] Hardness, as an important characteristic value of materials, is a scientific and technological characteristic value rather than a clearly defined physical quantity, and this characteristic value is usually determined based on the material sample. is defined as the resistance against indentation by a hard indenter. The inconsistency in the definition of hardness is already evident from the fact that in the case of metals only permanent indentation is evaluated, whereas in the case of synthetic resins and elastomers, indentation while applying a test force is evaluated. Furthermore, various indenters of geometrically simple shapes (e.g., spherical, conical, truncated conical, pyramidal) are commonly used, and the indenters are made of various materials (depending on their hardness range). For example, steel, diamond). Therefore, if a hardness testing method is to be available for the full range of material hardnesses, several criteria must be met. That is, the indenter must also be suitable for hardened metals, etc., and this only applies in the case of diamond.

Furthermore, the shape of the indenter must be geometrically simple and the shape of the indentation must be independent of the test force. Therefore, a spherical shape is not very suitable. In order to comply with existing standards, the use of conical (Rockwell C) or pyramidal (Vickers) shapes is preferred. However, since only the Vickers method is standardized for all (metallic) hardness ranges, the Vickers pyramid is particularly suitable for the general method.

Finally, for example in the case of elastomers (further synthetic l1i
The depth of the indentation must be measured under load, since after loading no or very few permanent indentations remain and therefore no hardness values can be obtained from this indentation. No. In the case of metals, only permanent deformation caused by an indenter has conventionally been understood according to standards. The elastic return upon measurement of the depth of the indentation (Rockwell C) is clearly discernible with the aid of a depth meter upon return of the total test force to the pre-test force. However, when measuring the diagonal of a Vickers indentation, the following assumptions are made:

This diagonal does not recover elastically at all, or at most only slightly, so that in the case of a Vickers indenter, from the depth of indentation measured while still under the test force, i.e. It is assumed that the length of the diagonal after unloading can be deduced while completely filling the created indentation.

As a result, in the case of the general hardness test method, a pyramidal hardness indenter made of diamond is used and the depth of the indentation is measured while still under the influence of the test force. Furthermore, since even the slightest abutment of the material specimen will result in falsification, and similarly elastic compression of the material specimen will result in falsification, in order to detect the depth of the indentation, the surface of the material specimen must be It seems essential to measure the difference in Furthermore, lateral displacements and changes in tilt of the material sample must be avoided, causing errors and sagging.

It is the basis of the invention that a device of the type mentioned at the outset be constructed in such a way that it satisfies the above conditions and can be used for general hardness testing over the entire hardness range. This is a challenge.

[Means and effects for solving the problems] According to the present invention, the above problems are solved by the following. That is, an indenter column loadable by a test force and supporting an indenter at one end is guided in an axially movable manner into a working leg tube, which can be raised relative to the material sample. A bearing is axially movably guided within the indenter column and is further provided with a depth tactile member for measuring the relative displacement between the indenter post and the operating leg tube, and the operating leg tube is The side end supports an operating leg penetrated by an indenter strut,
The operating leg has at least two bearing points supported on the surface of the material sample on both sides of the contact point of the indenter and located on a common straight line with the contact point, and is attached to the operating leg tube so as to be rotatable about a horizontal axis perpendicular to the .

When measuring the depth, the difference between the depth of dirt and the surface of the sample can be measured by the operation leg that comes into contact with the surface of the sample. Since this operating leg is supported on the surface of the material sample only in a straight line passing through the contact point, changes in the inclination of the surface about this straight line do not affect the depth measurement result.

The inclination of the surface of the material sample being pulled about an axis perpendicular to this straight line is adjusted by the rotatable mounting I'J of the operating leg in the operating leg tube, and at the same time the error This is not a problem as a cause. Additionally, measurements are taken while being subjected to a test force using a depth tactile member.

In particular, in the case of a pyramidal indenter, the rotation around the axis of the indenter support is m,! In order to do this, in a preferred embodiment the indenter column is rotationally blocked in the operating leg tube and the operating leg tube in the bearing body.

Roughly, a central member that is provided in the operating leg tube immediately above the operating leg and aligns the indenter column coaxially with the operating leg tube when the indenter column is removed from the material sample.
and further preferably guided in the operating leg tube only in the region of the upper end opposite to the material sample. The central member may be formed by a hollow conical ring in which the indenter post with the ring engages within its cone. Furthermore, in this case, if the indenter support is located in the central member, it is arranged such that the indenter protrudes somewhat beyond the bearing point of the operating leg at the most forward indentation point in the indentation direction facing the material sample. It is for a purpose that it is done.

As a result, during the measurement process, the indenter first contacts the surface of the material sample. The indenter post is then still in the central member and centrally located with respect to the operating leg tube. In the further course of the measuring process, the indenter branch is removed from the central member and the lateral movement thus obtained adjusts the measuring movement of the material specimen until the operating leg rests on the surface of the material specimen. be able to. In such a position, where the indenter is possibly loaded for the first time by a pre-test force, the value measured by the depth tactile member is standardized as the initial value and the depth indication is correspondingly set to zero. Ru.

A preferred mounting of the operating leg in the operating leg tube is characterized by the following: That is, the operating leg has a bearing surface on both sides of the axis of the operating leg tube, and the bearing surface rotates around a horizontal axis that intersects perpendicularly to the straight line between the bearing points at the point of contact of the indenter. Extending in a convex circular shape, the bearings are supported on each side of the apex of the surface under the force of a spring against a roll body attached to the operating leg tube. The spring bearing acts on the actuating leg above the axis of the plane, so that, in addition to its function of holding the actuating leg, this spring also performs a return function, which always returns the actuating leg to its initial position. .

The test force is generally applied in the form of a weight.

Further according to the invention, the bearing is fixed in body to a support plate which can be raised and lowered relative to the material sample, the support plate supporting at least one loosely attached weight for producing a test force. , the weight has a lifting member which overlies a stop of the indenter post located below the lifting member, and which lifts the lifting member upon lowering of the support plate relative to the indenter post. It is particularly provided that the weight is lowered onto said stop, thereby removing the weight from the support plate and transferring the force of the weight to the indenter post. Advantageously, the weight is constructed as a weight ring coaxial with the axis of the indenter support, the lifting member of which runs along the ring diameter lifting the operating leg tube and the indenter support in a window-like groove. Penetrate at. In order to easily vary the test force, a plurality of concentrically arranged weight rings are provided on the support plate, the innermost of the weight rings being provided with a lifting member. each of the other weight rings has a stop, which weight ring is removed from the support plate by means of the respective next inner weight ring by means of the collar, so that the lowering of the support plate is prevented. Depending on the degree, the weight ring is more or less effective on the indenter post.

In order to bring the indenter into contact, a pre-test force that is small compared to the test force (i.e., under the action of this pre-test force, the indenter penetrates the material sample to a depth comparable to that after being subjected to the full test force) In order to obtain (not yet possible), the indenter post is hung on the unloading carrier via a support,
The unloading carrier is held on the lifting member by means of at least one unloading spring, the force of the unloading spring being directed in the opposite direction to the gravity of the indenter column, and the displacement of the unloading carrier being is preferably limited in the direction of the force of the spring by a stop for the unloading carrier which is fixed to the lifting member. Advantageously, the unloading carrier is constructed as an arm-like lever attached to the lifting part H, on the free end of which an unloading spring and a stop act. As a result, depending on the unloading spring, it is easily possible to reduce the initially effective weight of the indenter column if desired at the beginning of the actual measuring process. Furthermore, a sensor responsive to the position of the unloading carrier relative to the lifting member may be provided, using which sensor the
A displacement drive provided for the support plate can be controlled. This allows us to first feed the indenter post into the material sample at high speed, but with a slightly more effective weight of the solder, but as soon as the indenter rests on the material sample and the sensor responds, we reduce the subsequent feed rate to the extreme. It is possible to lower it.

Additionally, a depth sensing member is disposed over the end of the indenter post on the operating leg tube and has a shaft coaxial with the indenter post, the shaft being a sensing member that abuts the end surface of the indenter post. It is preferable to have a section.

[Example] In the following, the present invention will be explained in detail using an example illustrated in the drawings.

In FIG. 1, 10 is a material sample placed on a table 32, and 2 is a hard indenter that can come into contact with the material sample 10 and first comes into contact with the material sample at the contact point. This indenter 2
is pyramid-shaped and made of diamond.

12 in order to measure the depth of the indentation in the material sample 10 caused by the indenter 2 subjected to the test force that loads the indenter 2 in contact with it.
A depth tactile member marked with is used. An indenter support 1, which is loaded by the test force and which supports the indenter 2 in one motion, is guided in an axially movable manner into the operating leg tube 5, roller bearings being used for this purpose. Similarly, the operating leg tube 5 itself is axially movably guided in a pair of rollers 37 in bearings that can be raised and lowered relative to the material specimen 10. The indenter support 1 in the operating leg tube 5 and its bearing in the body 6 are prevented from rotating, so that the pin 7 and the bearing in the indenter support 1 are prevented from rotating in the body 6. Pins 8 are used which engage corresponding longitudinal slits in the operating leg tube 5, and at the same time the axial length of said slits is equal to the indenter post relative to the operating leg tube 5. One axial movement area or bearing determines the axial movement area of the operating leg tube 5 relative to the body 6.

A depth sensing member 12 measures the relative displacement between the indenter post 1 and the operating leg tube 5. The operating leg tube 5 has an end on the sample side,
The operating leg portion 30 penetrated by the indenter support column 1 is supported. The operating leg 30 has at least two support points 11 supported on the surface of the material sample F3710 on both sides of the contact point of the indenter 20 and located on a common straight line with the contact point. In , it is formed by a spherical projection at the end of the operating leg 30 facing the material specimen 10 . Bearing point 11 without interfering with the measurement
It is possible to tilt between the operating leg and the material sample around the straight line connecting them. Further, the operating leg portion 30 is connected to the operating leg tube 5.
is rotatably attached to. To this end, the operating leg 30 must be mounted on both sides of the shaft 33 of the operating leg tube 5 with bearings mounted on surfaces 34.
, the bearing has a surface 34 extending in a convex circular shape around a horizontal axis perpendicularly intersecting said connection line of the bearing point 11 at the point of contact of the indenter 2, and the bearing has a surface 34 extending in a convex circle around a horizontal axis perpendicularly intersecting said connection line of the bearing point 11 at the point of abutment of the indenter 2; On both sides, it is supported by a spring 35 against a roll body 9 attached to the operating leg tube 5. The point of action of the spring 35 on the operating leg side is the operating leg 3.
0, so that the spring 35 simultaneously exerts a return force on the operating leg 301.

If the indenter post 1 has not yet been placed on the material specimen 10, the indenter post 1 is provided in the operating leg tube 5 directly above the operating leg 30 and connects the indenter column 1 with the operating leg tube 5. It is on the central member 4 which is aligned coaxially. Furthermore, the indenter post 1 is guided with a roll body 3 in the operating leg tube 5 only in the region of its upper end opposite the material sample 10. The central member 4 is a hollow conical ring in which the indenter post 1 with a corresponding ring engages within its conical shape. If the indenter post 1 is in the center member 4, the indenter 2 is
The forwardmost pushing point facing the material sample 10, that is, the apex of the pyramid, is located at the operating leg 3 in the pushing direction.
It protrudes slightly beyond the bearing point 11 of 0. The bearing body 6 is fixed to a support plate 13 that can be raised and lowered relative to the material sample 10.

This support plate 13 is fitted with three loosely attached weights 19. in the example to create a test force.
19°, 191 is supported. This weight is configured as a weight ring coaxial with the axis of the indenter support 1.

The innermost weight 19 supports a lifting member 18 extending along the ring diameter, which lifting member 18 passes through the operating leg tube 5 and the indenter post 1 in a window-like groove 20 and which extends along the ring diameter. extends over the stopper 36 of the
When the support plate 13 is lowered relative to the indenter column 1, the lifting member 18 is lowered onto the stopper 36,
This releases the weight 19 from the support plate 13 and transfers the force of the weight to the indenter post 1. The other two weight rings 19', 19'' each have one stop 37
When the support plate 13 is gradually lowered, each individual weight ring is removed from the support plate 13 by means of the stop 37 and in each case by the inner weight ring. Further, the indenter column 1 is hung on an unloading carrier 15 via a support 38, and the unloading carrier 15 uses an unloading spring 14 to lift the lifting member 1.
8, the force of the unloading spring 14 being directed opposite to the force of the weight of the indenter column 1. The unloading carrier 15 is constructed as an arm-shaped lever attached to a lifting member 18, on the free end of which an unloading spring 14 acts. Furthermore, a stop 11 associated with the free end of the lever of the unloading carrier 15
is provided on the lifting member 18, and the stopper 11 is
The movement of the unloading carrier 15 is restricted in the direction of the force of the unloading spring 14. A sensor 16 disposed on the lifting member 18 detects the unloading carrier 15 relative to the lifting member 18.
, in which case this sensor 16 is responsive to the position of the support plate 13 (not shown).
It is used to control the Ruri. Finally, depth tactile member 1
2 has a sensing part 12° which is coaxial on the operating leg tube 5 above the end of the indenter post 1 and abuts against the end of the indenter post 1.

To carry out the hardness test, the support plate 13 is first lowered as a whole in the direction towards the material sample 10 at a relatively fast feed rate. In this case, first the apex of the indenter 2 comes into contact with the material specimen 10 , whereby the indenter column 1 is raised relative to the operating leg tube 5 . Such a lifting releases the indenter post 1 from the central member 4, which allows the indenter 2 to perform a slight lateral movement, thereby lifting the operating leg 30 and the material sample F11.
0, a slight lateral movement of the material sample 10 relative to the operating leg 30 can be adjusted. Since the unloading carrier 15 is pulled upward by the force of the unloading spring 14, the indenter support 1 is moved upward. ′! li
When it comes into contact with o, it does not work with full gravity. When the support plate 13 is further lowered, the unloading carrier 15 activates the sensor 16, which switches the feed rate of the support plate 13 to a relatively low operating value determined for the test process. The unloading carrier 15 finally reaches a stop 17 by means of which the lifting member 1
8, the full gravity of the indenter column 1 becomes effective as a testing force during further descent. Further, as the support plate 13 continues to descend, the operating leg 30 is placed within the material sample 10. In this position, the value measured by the depth tactile member 12 is set to zero.

Material test around the connection line of contact point 11 P! 1.10 remains unaffected and the tilt about the axis perpendicular to this connection line is adjusted by the rotatable mounting of the operating leg 30 in the operating leg tube, so that the operating leg The section 30 can accommodate slight inclinations of the surface of the material sample 10 without risk of measurement errors. Support play 1~
13 continues to lower, the innermost weight ring 19 is moved through the lifting member 18 to the indenter column 1.
The indenter 2 is placed on top and under the gravity of this weight ring 19 creates a hardness indentation in the material sample 10. Depending on the desired test force, the lowering movement can be continued until the other weight rings 19°, 19°° are activated on the indenter column 1.

When calculating the hardness value, it is assumed that in the case of the Vickers hardness test, the indentations are always geometrically similar to each other, so that the detected hardness depends very little on the test force. Under this assumption, the total indentation depth can be determined from the known pre-test force and the test force, as well as from the measured depth increase in transition from the pre-test force to the test force. It can be calculated. From this depth, a central concavity diagonal and, with it, a Gockers hardness are obtained.

Correspondingly, an elastic return of depth can also be detected.

The hardness test device explained using FIG. 1 and FIG.
Advantageously, as depicted in Figures 3 and 4,
Can be extended to test systems. A base plate 21 supports a column 22, on which a rotationally prevented sleeve 23 is guided so as to be movable up and down using a spindle 25 via a servo motor 24. An upper sleeve 26 rotatable with respect to the lower sleeve supports on the one hand the support plate 13 of the hardness testing device corresponding to FIGS. 1 and 2 and on the other hand the measuring microscope 40;
Using the measuring microscope 40, the resulting hardness indentation can be optically inspected for control purposes and remeasured in the conventional manner. Advantageously, the specimen 10 itself lies on a controllable cross table 29, which further passes the located coordinate values to a 37 calculator. The calculator processes these coordinate values together with the hardness value and, as the case may be, calculates the course of the measured hardness (linear measurements during hardening, etc.) or the measured hardness pulses (seams, etc.). etc.) to a recorder or plotter.

[Effects of the Invention] According to the hardness testing device of the present invention, the depth of the indentation is measured while under the action of the test force, and the difference with respect to the surface of the material sample is measured to detect the depth of the indentation. Furthermore, lateral displacement and tilt changes of the material sample do not cause errors and can be used for general hardness testing over the entire hardness range.

[Summary 1 The device includes a hard indenter (2) that can come into contact with the material sample (10) and that contacts the material sample (10) for the first time at the contact point.
, and the indentation of the original indenter (2) into the material sample (10) under the test force can be measured. for that purpose,
An indenter post (1) loaded with a test force and supporting an indenter (2) at one end is axially movable in the operating leg tube (
5), whose operating leg tube (5)
The bearing that can be raised and lowered relative to 81 (10) is the body (6)
axially movably guided therein. A depth sensing member (12) measures the relative displacement between the indenter post (1) and the operating leg tube (5). The operating leg tube (5) supports an operating leg (30) at its end on the sample side, and the operating leg (30)
has at least two bearing points supported on the surface of the material sample (10) on both sides of the contact point of the indenter (2) and located on a common straight line with the contact point, and It is attached to the operating leg tube (5) so as to be rotatable about a horizontal axis perpendicularly intersecting the straight line at the contact point. The operating leg (30) can thus adapt to changes in the inclination of the material sample (10) without measurement errors in the depth of the indentation.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of the hardness testing device of the present invention depicting only the woody part, FIG. 2 is a partial view of the object in FIG. 1 in the direction of arrow X, and FIG. FIG. 4 shows a top view of the object of FIG. 3, respectively. FIG. Explanation of symbols 1... Indenter support 2... Indenter 3... Roller bearing (roll body) 4...
Central member 5... Operating leg tube 6... Bearing is body 7... Pin 8... Bin 9... Roll body 10. ...Material sample 11...Bearing point 12...Depth sensing member 12'...Sensing section 13...Support plate 14... - Unloading spring 15... Unloading carrier 16... Sensor 17... Stopper 18... Lifting member 19... Weight 19 '... Weight 19''... Weight 20... Window-shaped groove 21... Base plate 22... Support column 23... Sleeve 24... ... Servo motor 25 ... Spindle 26 ... Sleeve 29 ... Cross table 30 ... Operation leg 37 ... Roll body 32...Base 33...Axle 34 of the operating leg tube...Bearing is surface 35...Spring 36...Stopper 37... ...Stopper 38...Support 40...Measuring microscope patent applicant Zwick GmbH agent Patent attorney Tsuta 1) Sho Zi Idiot 1 person proceeding...Authentic letter (spontaneous) 1985 August 8th, Mr. Michibu Uga, Commissioner of the Patent Office 1
1. Indication of the case 1985 Patent Application No. 147600 2. Name of the invention Hardness testing device 3. Person making the amendment Relationship to the case Patent applicant Federal Republic of Germany 7900 Ulm/Donaulem Marweg 22 Zwick GmbH Representative Person: Wallentine Lambert Nationality: Federal Republic of Germany 4, Agent: 8th Floor 6, Harada Building, 2-9 Kawaramachi, Higashi-ku, Osaka 541
, Target of amendment Drawing 7, contents of amendment Figure 1 in the drawing is corrected as shown in the attached sheet.

Claims (1)

[Claims] 1. A hard indenter (2) that can come into contact with the material sample (10) and first contacts the material sample (10) at the contact point, and a load is applied to the indenter (2) in contact with the material sample (10). In an apparatus for testing the hardness of a material sample (10) made of metal, synthetic resin, elastomer, etc., the indentation of the indenter (2) into the material sample (10) can be measured under a test force of: An indenter post (1) loaded by and supporting an indenter (2) at one end is axially displaceably guided in a working leg tube (5), which handles the material sample. (10) is axially movably guided in a bearing body (6) that can be raised and lowered relative to the indenter support column (1) and the depth for measuring the relative displacement between the indenter column (1) and the operating leg tube (5). Tactile member (
12), and the operating leg tube (5) is provided with an operating leg (3) whose end on the sample side is penetrated by the indenter strut (1).
0), this operating leg (30) has at least two bearing points supported on the surface of the material sample (10) on both sides of the contact point of the indenter (2) and located on a common straight line with the contact point. (11), and is attached to the operating leg tube (5) so as to be rotatable around a horizontal axis perpendicularly intersecting the straight line at the contact point of the indenter (2). Hardness testing equipment. 2. The patent claim is characterized in that the indenter support column (1) is prevented from rotating within the operating leg tube (5), and the operating leg tube (5) is prevented from rotating within the bearing body (6). A device according to scope 1. 3. With the indenter support column (1) removed from the material sample (10), insert the operating leg (
30) and on the central member (4) which aligns the indenter post (1) coaxially with its operating leg tube (5), and furthermore in the region of the upper end opposite to the material sample (10). 3. Device according to claim 1, characterized in that the control leg is guided in the tube (5) only at the bottom. 4. Claim characterized in that the central member (4) is formed by a hollow conical ring, the conical shape of which is engaged by the indenter post (1) provided with the ring. Apparatus according to paragraph 3. 5. When the indenter post (1) is in the central member (4), the indenter (2) is inserted into the operating leg tube (3) at the forward-most indentation point facing the material specimen (10) in the indentation direction.
Device according to claim 3 or 4, characterized in that it projects somewhat beyond the bearing point (11) of 0). 6. The operating leg (30) is connected to the shaft (33) of the operating leg tube (5)
has bearing surfaces (34) on both sides of the bearing surface (34).
) extends in a convex circular shape around a horizontal axis that intersects perpendicularly to the straight line between the bearing surfaces (11) at the contact point of the indenter (2), and on each side of the apex of the bearing surface. Any one of claims 1 to 5, characterized in that the roll body (9) attached to the leg tube (5) is supported by the force of a spring (35). The device according to item 1. 7. The bearing body (6) is fixed to a support plate (13) that can be raised and lowered relative to the material sample (10),
The support plate (13) supports at least one loosely attached weight (19) for producing a test force, the weight (19) having a lifting member (18); covers the stopper (36) of the indenter post (1) below this lifting member, and the support plate (36) relative to the indenter post (1)
13), the lifting member (18) is lowered onto the stop (36) and the weight (19) is removed from the support plate (13). 6. The device according to any one of clauses 6 to 6. 8. The weight (19) is configured as a weight ring coaxial with the axis of the indenter post (1), and the lifting member (18) of the weight ring extending along the ring diameter is inserted into the window-like groove (20). 8. A device according to claim 7, characterized in that the operating leg tube (5) and the indenter post (1) are penetrated at. 9. Multiple weight rings arranged concentrically (19, 19'
, 19'') are provided on the support plate (13), and the innermost weight ring (19'') is provided on the support plate (13).
9) is provided with a lifting member (18) and each of the other weight rings (19', 19'') has a stop (37) by means of which said weight ring is then respectively 9. The device according to claim 8, characterized in that it can be removed from the support plate (13) by means of a weight ring located at the support plate (13).10. ), the unloading carrier (15) being held on the lifting member (18) by means of at least one unloading spring (14);
14) the force is directed opposite to the gravitational force of the indenter column (1), and the displacement of the unloading carrier (15) is caused by the unloading carrier fixed to the lifting member (18) in the direction of the force of the spring. Claims 7 to 9 are limited by the stopper (17) for (15).
Apparatus according to any one of paragraphs. 11. The unloading carrier (15) is constructed as an arm-shaped lever attached to the lifting member (18), and the unloading spring (14) and the stopper (11) act on the free end of the lever. 11. The device according to claim 10, characterized in that: 12, unloading carrier (15) relative to the lifting member (18)
) is provided with a sensor (16) responsive to the position of the
12. Device according to claim 10, characterized in that the sensor (16) is used to control a displacement drive provided for the support plate (13). 13. A depth sensing member (12) is disposed over the end of the indenter post (1) on the operating leg tube (5) and has a shaft (12' coaxial with the indenter post (1)). ), the shaft (12') of which is provided with a sensing portion that comes into contact with the end surface of the indenter support (1).
The device according to any one of Items 1 to 12.