DE1181255B - Process for the production of sheets or plates from an iron-silicon alloy with a crystallographically oriented structure - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: C21d

Number:
File number:
Registration date:
Display day:

German class: 18 c -1/78

G 30439 VI a / 18 c
September 6, 1960
November 12, 1964

The patent 1159 978 relates to a method for the production of sheets or plates from a Iron-silicon alloy, in which most of the crystallites have the (110) [001] orientation, in which an alloy of 2.5 to 4% silicon, not more than 0.035% carbon, 0.015 to 0.05% sulfur, at most 0.15% manganese, less than 0.1% titanium, the remainder being essentially iron to form a slab-like Block with a maximum thickness of 50 mm is poured in the block mold at room temperature cooled and heated again to about 1000 ° C for rolling. When warm the block is then rolled out onto sheets and strips less than 4 mm thick, which subsequently rolled down by more than 40% of its thickness when cold and then recrystallized to be annealed.

This process enables the manufacture of ingots that are cooled for storage and at any time can be reheated without affecting the crystallographic structure of the rolled End product suffers.

In the additional patent application G 25589 VI / 18 c (German Auslegeschrift 1176164) it is disclosed that there is a relationship between the speed of the ingot directly involved in the solidification of the ingot subsequent cooling of the ingot from about 1400 to about 800 ° C and the degree of crystallographic orientation that results in the rolled strip or sheet when one the ingot according to the main patent 1159 978 allowed to cool to room temperature and then it reheated and rolled out to form the strip or sheet.

If you froze after the instructions given by this additional patent application Ingot between about 1400 and about 800 ° C at a rate of at least 130 ° C per minute cools, the block can be according to patent 1159 978 to room temperature cool and then process to a sharp (110) [001] texture by manipulating it like it happens as mentioned in the patent 1159 978, heated again to about 1000 ° C, rolled out into a strip and this with the appropriate Heat treatment cold rolled to the end product.

It has now been found that a fine distribution of manganese sulfide can be achieved in an ingot consisting of the iron-silicon alloy specified and containing a certain amount of manganese and sulfur if the ingot is subjected to temperatures in processes for producing sheet metal or
Iron-silicon alloy plates with
crystallographically oriented structure
according to patent 1159 978

Addendum to the patent: 1159 978

Applicant:

General Electric Company, Schenectady, N.Y.

(V. St. A.)

Representative:

Dipl.-Ing. M. light,

Munich 2, Sendlinger Str. 55

and Dr. R. Schmidt, Oppenau (Renchtal),

Patent attorneys

Named as inventor:

Howard Charles Fiedler, Schenectady, N.Y.

(V. St. A.)

Claimed priority:

V. St. v. America September 16, 1959

(840290)

where the manganese and sulfur are in solution, for example from 1300 to 1400 ° C or higher cools about 1000 ° C at a rate between 50 to 130 ° C per minute. The finely divided Manganese sulfide inhibits grain growth during the final annealing and thus enables that a corresponding degree of crystal orientation is achieved. The metal can either be immediate from the liquid state in which it is after pouring into the mold, or be cooled from a temperature which is above the temperature at which manganese and Sulfur is usually in solution. The latter temperature is usually in Range from 1300 to 1400 ° C. Is the iron-silicon alloy from this or from temperatures above this range with sufficient speed cooled, so the manganese sulfide

409 727/294

Distributed in the cast block in such a way that no further heat treatment needs to be carried out. The ingot can then subsequently be rolled out to produce the desired texture.

In the drawing shows

F i g. 1 shows a graphical representation in which the dependence of the (110) [001] orientation (in ° / o) on the temperature (in ⁰ C) of the final annealing is shown on two bodies, one of which is cast from a graphite mold Block and the other is made from a block cast in a sand mold,

F i g. FIG. 2 is a graph similar to FIG. 1, one body having a velocity of 50 ° C per minute and the other is cooled at a rate of 130 ° C per minute has been.

To discuss the influence of temperature on the (110) [001] degree of orientation, the same Molten metal poured two blocks weighing 22.5 kg. One block of metal was turned into one Graphite mold and the other poured into a sand mold. The composition of the metal was 3.27% silicon, 0.026% sulfur, 0.057% manganese, 0.004% carbon, 0.009% oxygen, 0.002% Nitrogen and the remainder essentially iron.

The molds were 67 x 127 mm in cross section. The blocks became slices cut to a thickness of 25 mm, heated to 1000 ° C and closed without reheating rolled into a strip of 2 mm thickness. The tape was pickled, sandblasted and heat-treated at 900 ° C for 5 minutes. It was then cold rolled to a thickness of 0.6 mm, Heat treated at 860 ° C for 1 to 5 minutes and cold rolled to 0.3 mm.

The faster the cooling rate at which an ingot is cooled from the solution temperature of the manganese sulfide or from a temperature above this solution temperature, the smaller the manganese sulfide particles and the more effectively they prevent normal grain growth in the end product. For example, a material cast in a sand mold, processed to final thickness and heat treated at 950 ° C for 10 minutes has a grain size of approximately 0.038 mm, while a material cast in a graphite mold has a grain size of approximately 0.030 mm. To determine the cooling rates, 25 mm thick test disks were produced from the block cast in a graphite mold and from the block cast in a sand mold, which were heated above the solution temperature of manganese and sulfur (1300 to 1400 ° C) and then at speeds of 50 ° C per minute to 130 ° C per minute were cooled. The final product of the sample cooled at 130 ° C per minute had an average grain size of approximately 0.020 mm, while that of a sample cooled at 50 ° C per minute had an average grain size of approximately 0.028 mm. The end product made from the ^{material cooled at 50 °} C. per minute thus has essentially the same grain size as the product made from the graphite molds. It follows that the material cast in a graphite mold exhibits a cooling rate of the order of 50 ° C. per minute, while the material cast in sand has a considerably slower cooling rate.

The influence of the cooling speeds can be clearly seen from FIGS. 1 and 2, in which the The degree of texture is entered, which was obtained at the temperature shown after 2 hours. the Curve 10 relates to the material cast in a graphite mold. In this case, texture grades of over 80% when the material is heat treated in the range of approximately 925 to 975 ° C will. On the other hand, it shows the material made from a block cast in a sand mold and therefore cooled at a rate of less than 50 ° C per minute after Curve 11 only has a texture level of at most 40% when it is heat treated at 925 to 975 ° C.

In FIG. 2, curve 15 relates to a sheet which has been cooled from a sheet at 130.degree. C. per minute Material is made, while the curve 16 relates to a sheet metal made of a with material cooled at a rate of about 50 ° C per minute. Of the The degree of texture of the material cooled at 50 ° C. per minute essentially corresponds to that in the curve 10 of FIG. 1 specified degree of texture. The maximum value of the degree of texture achieved is in On the order of 80%, and the degree of texture drops quickly when higher temperatures occur at the Final annealing can be applied. It is important that the degree of orientation increases with increasing annealing temperatures drops, as this makes it possible to produce the texture in proportion to the annealing use low heating speeds. In the table, the developed degree of texture is in Dependency of the heating rate during final annealing shown.

Cooling rate
of the block
(° C / min)

50
130

Degree of texture in percent heating speed

25 ° C / hour or 00 ° C / hour 200 ° C / hour

82 88

70 85

71 84

At 950 ⁰ C, the development of the texture takes much longer than at a slightly higher temperature, for example at a temperature in the range of 1050 to 1100 ° C. at a rate of 130 ° C per minute cooled material usually develops a texture level of approximately 90% and a texture level of over 80% when the annealing temperature is increased to 1100 ° C. Thus, if the cooling rate for the deposition of a fine, grain growth-sustaining second phase, ie, for the deposition of manganese sulfide or other such inclusion, is kept high, a high degree of orientation can be easily and quickly developed by using higher temperatures. It has been found that at temperatures around 950 ° C, annealing times of the order of half an hour are required to develop an adequate texture, while at annealing temperatures of the order of 1050 to 1100 ° C or possibly a little higher, the texture development already after about 5 Minutes is complete. With a cooling

speed of 50 ° C per minute one can therefore achieve good (110) [001] textures, however can do even more with even higher cooling speeds of up to 130 ° C per minute Benefits can be achieved.

Claims (1)

Claim: Process for the production of sheets or plates from an iron-silicon alloy with (110) [001! -Orientation of the crystallites according to patent 1159 978, according to which an alloy of 2.5 to 4% silicon, at most 0.035% carbon, 0.015 to 0 .05% sulfur, in which the manganese content is at most 0.15% and the titanium content is less than 0.1% and the remainder consists essentially of iron, is cast into a slab-like block with a maximum thickness of 50 mm, which is cooled to room temperature and is reheated to about 1000 ° C for hot rolling, characterized in that the ingot of temperatures at which manganese and sulfur are in solution, for. B. 1300 to 1400 ° C and higher, mainly from about 1400 ° C at a rate between 50 and 130 ⁰ C per minute to about 1000 ° C is cooled. 1 sheet of drawings 409 727/294 11.64 © Bundesdruckerei Berlin