SU1758503A1 - High-temperature hardness gage - Google Patents

Description

one

(21) 4499404/28 (22) 10.31.88 (46) 08.30.92. Bul G 32

(71) Institute of Strength Problems of the Academy of Sciences of the Ukrainian SSR

(72) C. P. Kraschenko and O. B. Oxametna

(56) USSR Author's Certificate NJ S3254, cl. G 01 W 3/54, 1950.

(54) HIGH-TEMPERATURE SOLID DOMER

(57) The invention relates to a test technique. The purpose of the invention is the expansion of technological capabilities. The installation contains a sealed chamber, including a plate, a sample loading unit with a rotatable holder and a multi-ped, an index moving mechanism, the leash of which is connected to the holder, and its drive, a furnace mounted on the plate, including a muffle with a nest for mounting and a sample, a heating element distributed inside the muffle, casing and body. A new device is an L-shaped holder, the leash is connected to the holder in such a way that the tip of the indenter lies on its axis, and the center of mass of the load point is aligned with the tip of the indenter. The installation is equipped with a rotary drive furnace installed on the stove, the furnace casing is interconnected with the ups of the 1st turn of the furnace. The muffle is rigidly connected to the upper part of the casing, between the housings and the muffle, tubch screens are installed around the casing. The drive of the movement mechanism with respect to the driver is oriented at a right angle, and the drive of rotation is set axially with the axis of the furnace, 8 ° L.

The invention relates to testing equipment, in particular, devices for determining the hardness of materials at PSC temperatures in a vacuum or protective gas environment, and can be used in laboratories for the study of the mechanical characteristics of materials.

A known device for determining the hardness of materials contains a rotary table, designed to mount a disk-shaped sample on it, and a device for applying radial scratches on the sample surface, made in the form of a spring-loaded and loadable replaceable weight rod with an indenter mounted above the sample. In this device, the indenter moves across the sample in the radial direction. The kinematic circuit of the instrument loading shows

that when introducing an indenter and then moving it across the surface of the sample, a certain amount of influence on the hardness value will have a strainer F of material resistance to movement of the indenter during scratching.

A microhardness tester is also known that can be tested using the scratch method. It is equipped with a coordinate movement mechanism that ensures the movement of the holder with the indenter in mutually perpendicular directions. The kinematic diagram of the instrument hyponloading is shown in FIG. b Appendix The loading sprig is designed in such a way that a scratch can be applied to the specimen in the direction of the axis of the axis, which is reinforced by an endochtor. and in the perpendicular axis of the lever direction. Sample at the same time

r - a

remains motionless. The advantage of such a device is that the force F of following a material to the movement of an indenter does not create an additional moment relative to the axis of the lever.

Since the rigidity of the movable part of the loading device in two mutually perpendicular directions is different, this does not allow creating the same conditions when scratching the surface of the sample in these two directions, which affects the accuracy of determining the accuracy

The closest in technical essence and the achieved result to the invention is a high-temperature hardness tester that contains a vacuum chamber, an object with a goal for fastening a sample, a thimbler, a rotating holder with an indenter and interchangeable weights and an indenter movement mechanism along the sample surface, made in the form of a housing, a drive mounted therein in a reciprocating movement with a leash associated with the axis of rotation of the indenter holder and the stop mounted to cooperate with the tool holder. The test specimen with thin section is placed in the nest of the furnace and subjected to scratching on the spindle with the tip of the indenter with a load that is resolved by means of a uniformly rotating screw.

The advantage of the device in comparison with the known ones is the possibility of carrying out tests for microhardness according to the method of scratching both at room temperature, on the hook and on heating.

However, the device has a number of flaws, the main point of which is that it does not allow to determine the static hardness of the studied materials.

The purpose of the invention is the expansion of technological capabilities by defining and static verdict.

The goal is achieved by the fact that in an apparatus for determining the hardness of materials at high temperatures, containing a vacuum chamber, a sample table for fastening a sample, a heater mounted for rotation of the holder with replaceable weights and an n rvieuie mechanism of an indenter along the surface of oooism , made in the form of a housing, a drive of reciprocating movement in it with a lead connected to the axis of rotation of the holder of the indenter Y, the stop mounted with according to the invention, it is equipped with

the leash and spring-loaded relative to the housing of the movement of the indenter with a rod with trunnions connected with it and pivoted with a holder with a groove lever

In this case, the pins are located in the groove of the lever, and the support is located on the lever

Such an embodiment of the device makes it possible to determine the hardness both by the method of scraping and by the method of indentation, so that its technological capabilities

FIG. Figure 1 shows an installation for determining the hardness of materials at high temperatures k, longitudinal section; FIG. 2 is the same, right side view, along and apart 5 times: FIG. 3 - the mechanism for moving the indenter (in a sectional view from above, on 4 - a kinematic diagram of the mechanism for moving the holder with the indenter in the initial position and when applying a scratch;

The appendix 0 shows the kinematic diagram of the loading of analogue 1 (Fig. 5), analogue 2 (Fig. 6), the prototype (Fig. 7) and the claimed installation (Fig. 8).

Hardness test

5 materials at high temperatures contains an airtight chamber 1 consisting of a plate 2 and a casing 3, inside of which there is a sequence of longitudinal separation 4 / with an endgore 5 Mechanism 4

0 longitudinal displacement contains chorP 5, & OiOpGM WOULD BE FLOOR PV-jLO, ESCHIL P

Cf. whose cuior tooTi / i are mutually perpendicular to the vertex / s, in which 7 are located, interacting with 5 lines (not shown), and in the other hole there is a new port with 8, with One side of the stios g uko ° n- with the possible, ya hey jcora chsrjecha and

a C - ShGOK 10, VOCi JO LINK | CH1I S

0 carriage 1 is supplied-on / - 12 (see Fig 3), carriage 11 is spring-loaded with respect to orp; ca 6 springs, mi 1o I and charoter is also set to vlore 15 so that one t rn end has

5 turns around 9 turns 1, and the other has BOCsJoC | bcccc pin 12 and from oppf 12 top. At the same time, the axle axis is perpendicular to the PORODX axis 8. The stop 5 /;

0 by the possibility of a vaimodeis vi / s gai 9, the lever is connected with the ip-oh 10 p and 10 ghzhoykh otoh / gogo element 17 which is supported 18 the axis of the pivot 8 and the axis of rotation of the holder 19 res5 laid out from the plane of the horizontal greztsa 20

The system on the ru, nor the ind t it from the Dyuh flat fuzol 2 {. c ,, - r L godi from diu sides r, r w v pooorannyh ga. im oOD5zo.

the masses of the entire loading system coincides with the tip of the indenter 5.

On the plate 2 there is a rotatable electric night, which includes fixedly mounted on the plate 2 are cooled1 case 23 with heating element 14 and current lead 5 and a set of internal 25 vi outer 27 screens rotating around its axis, casing 28 with a muffle 30 fixed on it, in the slot of which sample 20 is installed.

The installation is equipped with a rotational drive, including a gear wheel 3 i, located with the furnace axis on the housing 23 with the possibility of rotation around its axis, and the gear shaft 32, which interacts with it. Gear 33 is also mounted on gear shaft 32 (on the opposite side of plate 2) and interacts with gear wheel 29.

The shielding gas is introduced into the chamber 1 or a vacuum is created in it through the nozzle 34.

If it is necessary to apply a scratch in only one direction (from the center to the periphery), an emphasis 15 is provided;

Tests on the proposed plant are carried out as follows. Sample 20 with a thermocouple (not shown) is installed in the socket of the muffle 30. The springs 13 while holding the carriage 11 in the extreme right position. The chamber 1 is closed with the casing 3 and through the nozzle 34 the air is evacuated from it. After reaching the required vacuum (10 Pa), the heater 24 is supplied with current leads 25 located on the flange 23, and the sample is heated to a predetermined temperature. Then, a displacement drive is turned on (not shown), which drives the pull 7, which, in turn, moves the rod 10 with the carriage 11 and the lever 14 mounted on it with the help of a flexible elastic element 17. When moving the carriage 11, the lever 14 is deflected, the stop 15 is displaced from the holder 9, the indenter 5 loaded with weights 21 located on the crossbar 22 is lowered and inserted into the sample 20 (see Fig. 4). Next, the carriage 11 contacts the driver 8 and the rod 10 moves together with the carriage 11, the driver 8, the holder 9 with the loads 21 and the indenter 5 placed on it, as a result of which

scratch. When the extreme left position of the leash 8 is reached, the drive is moved (it is switched on. Then the rotation drive is turned on (not shown in the drawing), the bridges of the straight B movement the shaft gear 32, and the gear 33, I.OKT P with the toothed knee 29 ks -, ulp 28 By this, the casing 28 and the prisoner of oh-em are set - - fel 30 with a sample of 20 civilians / h, h with i

given yon, which co-rolls with -to kosho angle indicator. The dog from the camp includes shifts, - and, [PGO] ;; U per mechezt chgu Pru - kina 13 became Steel mva 1 -. - netku I about. sg

(right 1-) position, language, lie ,,.,. and “in the axis 16, 3, and -; there is the whole position, the support 15 is sticking to it. -t- rust 9, g ss-3 holder 9 -pipe-; - l indenter 5 rises. Zate systems: pi

vodka-power moves the b indicator to its initial rightmost position. The installation is ready for the next scratching. When examining the dependence of the hardness of materials on the temperature, scratches are applied to the sample at different temperatures at a certain angle relative to each other in the radial direction. If it is necessary to apply L.apf T | .1, in both directions Lx (on and backward), it is enough to fipi the help of screw 35 to connect bolt 10 with the leash 5 to the position when there is no gap between the 1 ends. After applying a series of scratches, the power supplied to the current leads 25 is disconnected. The chamber 1 is cooled, the housing 3 is removed, and the sample is removed using a 20 Nz microscope; the scratch width is measured and the hardness values are calculated from it using

a well-known formula, for example, for an indenter with a tip in the form of a four p & n pyramid with a square base when scratched with an edge

Nor -

0.3782 F.

about

B

where F is the normal load, N applied to the tip, -v- width of the groove in m, h, Appendix B shows the distribution schemes of the forces acting on the indicator when it is inserted — still, -the sample for two analogs (fmg . 5 and 6). prototype (figs, 7} and pre / taraeMoro device (fig 8), where: P - load onto end; R - force of material resistance of sample material to indentation; F - force of material resistance of sample material; inedeekiyu indenter; F - force of material resistance of sample material to indenter movement by his

surface; I - shoulder, which is assumed to be 1. In fig. FIG. 5 ... 8 are also shown for each of the schemes for charging the equilibrium equation of these forces with respect to point A (Fig. 1, axis 16), from which it can be seen that the loading circuit of the proposed installation is the most rational, i.e. the mutual arrangement of the load, the leash, the holder and the indenter eliminates the occurrence of the moment created by the force A of the material’s resistance to the movement of the indenter, which considerably reduces the vibration during scratching.

The installation provides the ability to study the hardness of materials by the indentation method. To do this, it is necessary to secure the leash 8 in the housing 6 with the help of the screw 36. At the same time, after insertion of the idler 5 into the sample 20 and some holding of the indenter 5 under load, the displacement drive is turned on again. The spring 13 pushes the carriage 11 to its original (right) position. The lever 14, turning around the axis 16, occupies a vertical position, the stop 15 touches the holders 9, and the holder 9 itself rotates and the indenter 5 rises 4 Then the rotational drive is activated, which drives the gear wheel 32 m additional gear 33 contacting with the toothed wheel 29 of the casing 28. At the same time, the casing 28 and the muffle 30 installed therein with the sample 20 are rotated to a predetermined angle, which is controlled by the angle indicator 31. The installation is ready for the next application of the print.

and

15

The number of hardness by the static indentation method of the pyramidal indenter is determined as the average pressure per footprint area from the formula

Fb2b2

Claims (1)

where P is the load on the sample, transmitted through a pyramidal indenter, N; F-area of the pyramidal imprint surface, mm; 2-angle between opposite edges of the pyramid (136 °); in - the arithmetic average of the two diagonals of the print, mm. Claims of Invention A high-temperature hardness tester comprising a vacuum chamber, a sample table placed in it, a heater, a rotatable holder with an indenter and interchangeable weights, and an indenter movement mechanism along the sample surface, made in the form of a case, and the actuator installed in it is reciprocating. - translational movement with a leash associated with the axis of rotation of the holder of the dei tore, and a stop mounted for engagement with the holder, characterized in that In order to expand technological capabilities by means of determination and static hardness, it is equipped with a current installed in a leash and spring-loaded in a leash and spring-loaded relative to the body of the movement of the indenter with trunnions connected with it and hinged with a holder with a groove, while the trunks are placed in the groove of the lever, and place the emphasis on the lever. 20 25 thirty 35  "3 t-v -" 5D v eat "NS CM CO about in 00 LO G-8 / J Lch-, -. „„ „. U„ .... „, (pus 5 EML P i-fiSt-Fl-O // d -  Јыл.7Ь Fig 7 LHA a P-3t- I MR AND # // sch R P four