DE1433766C - Process for the production of anisotropic permanent magnets with an axial crystal texture - Google Patents

Description

Table 1.

Lower part

Middle part

upper part

, cut is the same as that of the bar to be formed. In the (BH) _max value of about 5-10 * to 8-10 ⁶ G-Oe

In the present case, the rod has a diameter (coercive force 710 to 780 Oersted, remanence 12 500

on about 10 to 200 mm. The crucible 4 is from one to 13,200 gauss). It is also shown that in one

Surrounding the hole frequency coil 6, which from a non-constant waiting time of 30 seconds of the (BH) _ma x-

The current source shown is fed and the value of about 5 10 ^e G Oe to 8.8 -10 ⁸ G-Oe an-

Zrzeugen a melt 7 of the material 1 is used. By increases (coercive force 710 to 790 Oersted, remanence

: u prevent the melt from being attacked by gases from 12 500 to 13 600 gauss) when the speed

vird, especially of oxygen, the upper one is during the drawing step from 10 to 2 mm / sep

"Part of the crucible 4 with an inert or non-oxy- decreases. In general it can be said that

iating atmosphere filled, e.g. with argon, io for a predetermined value of (BH) _m ax,

ielium or hydrogen, which gas is replaced by a z. B. between 8.0 and 8.5 · 10 ^s G · Oe, the waiting time

inlet opening 8 enters and through an outlet, the longer the greater the speed

opening9 is discharged. The crucible 4 is of one during the pulling step.

/ Arm-insulating jacket 10 surrounded. The following table gives an impression of

A second (resistance) heating coil 11, wel- 15 the similarity of the magnetic properties,

he for determining the direction of discharge of the erosion, which is measured on long pulling rods. the

heat, surrounds the pipe 5 and magnetic properties of three parts (the

Λτά fed from a power source, not shown. lower, middle and upper part) of a rod with

) The lower end of the tube 5 is indicated by a bolt 12 of a length of 2 m, the

developed, which can consist of iron. The alloy is similar to that of the previous examples. bolt 12 is axial movement by two M
bands 13 issued, which move at variable speeds in step-by-step motion by means of suitable,
η rotated known feed mechanisms

can ground. 25 ~~

From Fig. 2 it can be seen that the tube 5 has a speed

λ λ Ii ττ ι · ι 11 5 mm / sec

Solidification zone 14 is limited. To practically every waiting time 30 seconds

heat of solidification in the axial direction to the molten.

; to withdraw a material, the one in the solidification (BH)

ingszone formed by a magnetic bar with 30 β ^ma * '

Water-cooled device 15 suitably con- jj

ruction led. · - · · ·

After the rod 16 is between the rollers 13

n is carried out, it arrives in a device 17 in which

• in the usual way by heat treatment at 35 speed

is made magnetically anisotropic in a magnetic field. ³ mm / sec

The rod is then cut into pieces with a waiting time of 30 seconds , which are finally magnetized.

In the device described above {BH) _m ax was

; m rod 16, which has a diameter of about 14 mm 40 ~ Z

Ute and an alloy of 24% Co, 14% Ni, " ^c

Vo Al, 3% Cu, 0.5% Nb and the remainder iron with the

common production-related impurities

and, issued a discontinuous movement. According to speed

; r heat treatment were magnetic bodies with 45. 5 mm / sec

The length of about 15 mm from the rod 16, waiting time 60 seconds

cut and axially magnetized. In Fig. 3 are the -

indicated for the procedural steps used. The (BH) _max

jspeed during the pulling step (d in B _r

m / sec) is on the vertical axis and the waiting so H _c

iten (t in see) are plotted on the horizontal axis. From this table it is evident that in any case the From this Fig. 3, in which the results of the scattering in the (BH) _max * values within ignetischen measurements with respect to the (BH) _ma x 0.5 x 10 ^e G · Oe can be kept, which are given for a srt in MG · Oe, the following can be accepted 55 Mass production is acceptable By improved: Control of the process, a smaller tolerance 3 can be achieved at a constant value of the speed, e.g. 0.2 to 0.3 -10 ⁶ G-Oe. During the drawing step of 10 mm / sec, the spread of the coercive force and the remanence of the waiting time of 30 to 180 seconds is generally below 1%.

7.2

13 420
765

2.

7.7

13 500
775

13 400 765

Lower
part

6, p

13100
785

3.

Middle part

7.1

13 150
785

upper part

12 960 770

Lower
part

8.4

13 720
770

Middle part

8.4

13 770
765

upper part

8.6

13 640 775

1 sheet of drawings

Claims (1)

ϊ 2 (57 /) maarWert is naturally due to the joint patent claim: Settlement of the alloys used is conditional. It should be noted that the (BH) _max -WeTt of the Process for the production of anisotropic permanent-achieved degree of axial crystal orientation abmagnete with axial crystal texture from a 5 is pending in the sense that (BH) max values above Ni-Al-Co-Fe alloy, in addition to the 6-10 ⁶ G-Oe with a high degree of crystalline impurities 15 to 42% Co, 10 until orientation can be achieved. If there is no crystal-20% Ni, 6 to 10% Al and optionally additives, orientation is present, the CSifWi-value such as up to 8% Cu, up to 4% Nb and up to 8% Ta, is about 4.5 to 5-10 ⁶ G · Oe. Between the last one, the niobium and / or tantalum content io mentioned (5 #) _m oz-value and the (BH) _max -WeTt can be partially replaced by titanium ^ at that of 6 · 10 "G · Oe lies one Path in which the alloy occurs in the closed state with partial crystal orientation and in which the upper end of a tube is thus fed and in the solid. The method according to the invention can also be used in the form of a rod at the lower end. of the pipe is discharged discontinuously, 15 The rods can be discontinuously removed from a pipe wherein the pipe wall is heated to such a high temperature with a length of about 10 cm at a rate is that the heat can be drawn essentially in speed from 0.1 to 10 mm / sec, the is removed in the axial direction, resulting in waiting times between about 10 and 200 seconds characterized in that the rod can fluctuate gradually in the sense that the lower at a continuous speed of 20 speeds with shorter waiting times ver-0.1 up to 10 mm / sec is pulled out of the pipe. If these conditions, in particular the waiting times between the drawing steps or the minimum waiting time are not met, the higher the drawing speed, the bars with poor surface quality will be and be at least 10 seconds. that often breaks when moving 25 go. In these cases there is practically no crystal orientation on, and accordingly is the (5 //) _maar value less than 5-10 ⁶ G- Oe. Should z. If, for example, a (BH) _max value of about 8 · 10 ⁶ G · Oe can be achieved, the pulling speed can The invention relates to a method for producing 30 10 mm / sec with a subsequent waiting anisotropic permanent magnets with an axial crystal texture time of 180 seconds. If this (BH) _max value is to be made from a Ni-Al-Co-Fe alloy, which is achieved in addition to a drawing speed of 5 mm / sec, the usual impurities 15 to 42% Co, 10 to 10, the waiting times must accordingly shorter, 20% Ni, 6 to 10% Al and optionally additives, e.g. B. between 30 and 60 seconds can be selected, such as up to 8% Cu, up to 4% Nb and up to 8% Ta, 35 If at these drawing speeds contains shorter, the niobium and / or tantalum portion waiting times are selected, results in a lower can be partially replaced by titanium, in which the (5H) _m os value. The same effect occurs when, in the case of an alloy in the molten state, greater drawing speeds are added to the end of a tube for the same waiting time and are selected in the solid state. in the form of a rod at the lower end of the tube 40 The method according to the invention will now be carried out is discharged discontinuously, the pipe wall being explained in more detail, for example with reference to the drawing, is heated to such a high temperature that the F i g. 1 shows schematically a device for Heat dissipated essentially in the axial direction. Carrying out the method according to the invention;
will. F i g. Fig. 2 shows a part on an enlarged scale In one of the Austrian patent 45 of the device according to FIG. 1; 210 909 known method of this type is shown in FIG. 3 shows an overview of a number of Stick at intervals of 1 minute by about 0.5 cm measurement results with a step-wise drawn pulled out of the additionally heated tube. Magnets. It has now been found that in this production process. 1 is granular material 1 from a move the drawing speed and the intermediate alloy for the magnet to be produced in one lying waiting times for the desired magne filling device 2 housed, from which it means tables and mechanical properties of the drawn a screw 3 is fed into a crucible 4. the Rods are important and that in most cases the screw is operated at a controllable speed both factors cannot be chosen arbitrarily. a drive mechanism, not shown, according to of the invention is the method initially 55 turns. Alloy 1 can consist of about 15 to 42% of the type mentioned, characterized in that the rod is cobalt, about 10 to 20% nickel, about 6 to 10% Gradually with a continuous speed of aluminum with up to 8% copper and / or of your choice up to about 4% niobium and / or up to 8% tantalum drawn from the tube from 0.1 to 10 mm / sec with the waiting times between the drawing, with the niobium and the tantalum content 60 can be partially replaced by titanium, while and be at least 10 seconds. the rest of iron with the usual manufacturing The invention is therefore based on the knowledge that conditional impurities exist. In the exemplary embodiment that describes the waiting time inserted between the drawing steps, the longer the drawing speed, the longer the drawing speed, the larger the alloy with 24% cobalt, 14% nickel, 8% aluminum. This means that 65 minium, 3% copper, 0.5% niobium and the remainder iron magnets with predetermined (BH) max values of can be used. over 5-10 ⁶ G-Oe, in particular more than The crucible 4 consists of a ceramic funnel, 6-10 ⁶ G-Oe. The maximum achievable which opens into a ceramic tube 5, the transverse of which