US3282661A

US3282661A - Composite metallic plates of titanium and dissimilar mother metals

Info

Publication number: US3282661A
Application number: US389822A
Authority: US
Inventors: Kawai Masayoshi; Kizuki Kiyohiko; Hara Hideo; Kobayakawa Hachiro; Shimizu Kameichi
Original assignee: Mitsubishi Steel Mfg Co Ltd
Current assignee: Mitsubishi Steel Mfg Co Ltd; Mitsubishi Steel KK
Priority date: 1962-03-29
Filing date: 1964-08-10
Publication date: 1966-11-01
Anticipated expiration: 1983-11-01
Also published as: GB1042603A; DE1283546B; GB1042604A

Description

"Nov. 1, 1966 MASAYOSHI KAWAI ETAL 3,282,661

COMPOSITE METALLIC PLATES OF TITANIUM AND DISSIMILAR MOTHER METALS Filed Aug. 10, 1964 2 Sheets-Sheet 1 Nov. 1, 1966 MASAYOSHI KAWAI ETAL 3,282,661

COMPOSITE METALLIC PLATES 0F TITANIUM AND DIS-SIMILAR MOTHER METALS Filed Aug. 10, 1964 2 Sheets-Sheet 2 United States Patent 3,232,661 COMPQSITE METALLHC PLATES 0F TITANIUM AND DlSSIMlLAR MOTHER METALS Masayoshi Kawai, Kiyohiito Kizuki, Hideo Hara, Hachiro Kobayalcawa, and Kameichi Shimizu, Nagasaki, Japan,

assignors to Mitsubishi Seiko Kabushiki-Kaisha, Tokyo,

Japan, a Japanese company Filed Aug. 10, 1964, er. No. 389,822 Claims priority, application Japan, Mar. 29, 1962, 37/12,387, 37/12,388 5 Claims. (Cl. 29196) This application is a continuation-impart of our applications Serial No. 266,998, filed March 21, 1963, now abandoned, and Serial No. 266,999, filed March 21, 1963, now abandoned.

This invention relates to a composite metallic plate made up of titanium and a dissimilar mother metal and more particularly to such a plate which has a titanium veneer bonded to a plate of dissimilar mother metal either directly or through an intermediate layer of bonding metal.

Titanium has many uses because it has excellent anticorrosive properties with respect to various media, high resistance to corrosion in the voids thereof, at boundaries, at stress points and at contact points and the like, and it is light in weight, has high strength and can be given a brilliant lustre. Thus, as a corrosion resisting metal, titanium has an important position in manufacturing chemical apparatus and other machines used in the fields of industry utilizing sea water, the petrochemical industry and the like. In addition, it is increasingly utilized for ornamental purposes and in manufacturing parts of medical apparatus and aircraft.

From an economic standpoint, in order to save expensive titanium and for purposes or rigidity, stiffness, weldability, strength and the like required in structures where titanium is used, it is frequently desirable to provide .a composite metallic plate having a titanium veneer bonded to a plate of dissimilar mother metal on either face or on both faces.

Heretofore, numerous processes for bonding a titanium veneer or llaminating a veneer to a sheet or plate of dissimilar mother metal have been proposed and are presently being used.

As is well known, titanium is different from many other metals in that it is very high in its chemical reactivity. Accordingly, it is recognized that joints between titanium and other metals become brittle, with the result that it is very difficult to ensure good adherence of the metals at such joints. This is principallybased upon the fact that titanium has very high affinities for oxygen, hydrogen, nitrogen, etc. and that, when titanium contacts any dissimilar metal to form therewith an alloy which comprises very frequently an intermetallic compound, there are many cases either where the titanium lamination exfoliates from the plate of dissimilar mother metal during veneering or where the resulting product has poor workability.

Accordingly, it is the chief object of the invention to provide an improved composite plate of titanium and a dissimilar mother metal having good adherence between the metals and excellent workability.

With this object in view, the invention resides in a composite metallic plate having a titanium veneer bonded either directly to a plate of dissimilar mother metal on at least one face, or through said plate of dissimilar mother metal to a base plate of dissimilar metal. When the mother metal is used as a bonding material it is an alloy consisting essentially of iron and a metal taken from the group consisting of .3 to 19.0% by weight of molybdenum, from .3 to 20.0% by weight of vanadium, from .3 to 15% 3,282,661 Patented Nov. 1, i966 by weight of niobium, from .3 to 8.0% by weight of zirconium and from .3 to 18.0% by weight of tungsten. When the mother metal is not bonded to a base plate, the mother metal is an alloy consisting essentially of iron and a metal taken from the group consisting of from .3 to 10.0% by weight of molybdenum, from .3 to 10.0% by weight of vanadium, from .3 to 10.0% by weight of niobium, from .3 to 6.0 by weight of zirconium, and from .3 to 10.0 by weight of tungsten respectively.

The invention will be more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic side elevation view, partly in cross section, of an assembly of a titanium veneer, a base plate of dissimilar :metal and an intermediate layer of dissimilar mother metal acting as a bonding material disposed therebetween, the assembly being processed in accordance with the teachings of the invention;

FIG. 2 is a view similar to FIG. 1 but illustrating a modification of the invention in which two plates are produced at the same time;

FIG. 3 is a schematic side elevation view, partly in cross section, of an assembly of a titanium veneer and a plate of dissimilar mother metal, the .assembly being processed in accordance with the teachings of the invention; and

FIG. 4 is a view similar to FIG. 3 but illustrating a modification of the invention in which two plates are produced at the same time.

The invention is based upon the discovery that particular iron alloys will adhere excellently to titanium.

According to the teachings of the invention a composite metallic plate having a titanium veneer or lamination is bonded either directly to .a plate of dissimilar mother metal or through said plate to a base plate of dissimilar metal as will be in detail described hereinafter.

As a result of an enormous number of experiments conducted over a long period of time, it has been found that a variety of iron alloys can be used as metallic bonding materials, the iron being alloyed with a metal taken from the group consisting of molybdenum, vanadium, niobium, zirconium and tungsten, to form composite metallic plates with titanium. As base metals for such composite metallic plates there can be used iron and steel materials such as ordinary steels and low alloy steels, for example ASTM type A201GB steel.

Where a mother metal is used as a bonding material between a titanium plate and a base plate, the metal of the abovementioned elements which is used should be contained in the bonding iron alloy in an amount of at least 3% based upon the total weight of the alloy. In the case where molybdenum, vanadium, niobium, zirconium or tungsten is used, in an amount less than 3% by weight in the iron alloys used as intermediate bonding metals, the results of the experiments indicated that the resulting products were poor insofar as adherence of the mother alloys which were used to the titanium was concerned.

On the other hand, the upper limits for the amounts of the aforesaid respective metals contained in the iron alloys have been determined by the deformability of the bonding iron alloys when the resulting products have been subjected to various mechanical workings. In other words, the upper limit for the content of a particular metal as above described has been determined by a compromise between the amount thereof and the respective amounts of carbon, manganese, silicon, phosphorus, sulfur etc. originally contained in the iron alloys used as bonding materials so as to impart to the iron alloys a workability .as compared with the base metal such that the finished composite metZlllilC plates will not be brittle.

Thus the upper limits for the amounts of the elements referred to in the iron alloys used as bonding materials have been determined to be 19%, 20.0%, 15.0%, 8.0% and 18.0% for molybdenum, vanadium, niobium, zirconium and tugnsten respectively, these percentages being based upon the total weight of the alloy.

In order to obtain a correlation between the amount of each of the abovementioned elements contained in the bonding iron alloys and the adherence properties of the alloys with respect to titanium, additional experiments were conducted. As a result, it has been found that as the amount of each element contained in the iron alloy is increased up to a certain limit, the adherence of the alloy to titanium is increased to a certain extent, with a further increase in the amount of the element beyond the limit not appreciably varying the adherence of the alloy. Also from both the phase diagrams for the iron alloys and the experiments it has been verified that any excess of the alloying elements adversely affects the hot workability of the bonding materials when bonding sheets are prepared. Therefore, considering all three aspects, adherence, economy and workability, the amounts of molybdenum, vanadium, niobium, zirconium and tungsten should preferably range from 1.0 to 5.0%, from 1.0 to 5.0%, from .5 to 2.0%, from .5 to 2.5% and from 1.0 to 2.0% respectively, on the basis of the total weight of the alloy.

It has also been found that a variety of iron alloys can be used as mother metals without further bonding to a base plate, the iron being alloyed with a metal also taken from said group consisting of molybdenum, vanadium, niobium, zirconium and tungsten to form composite metallic plates with titanium. The amount of any one of such elements contained in the iron alloy should range from .3 to 10.0% for each of molybdenum, vanadium, niobium and tungsten, and from .3 to 6.0% for zirconium, based upon the total weight of the alloy.

When the mother metal was used without further bonding to a base plate, where any one of molybdenum, vanadium, niobium, zirconium and tungsten was present in an amount less than .3% by weight of the iron alloy used as the mother metal, the results of the experiments indicated that the resulting products were poor in adherence of the mother metal to the titanium. On the other hand, the upper limits for amounts of the aforesaid respective elements contained in the iron alloys have been determined by the deformability of the mother metals or iron alloys when the resulting products were subjected to various mechanical workings. In other words, the up per limit for the content of a particular element as above described has been determined by a compromise between the amount thereof and the respective amounts of carbon, manganese, silicon, phosphorus, sulfur etc. originally contained in the iron alloys to be used as mother metals so as to impart to the iron alloys a workability such that the finished composite metallic plates will not be brittle.

In order to obtain a correlation between the amount of each of the abovementioned elements contained in iron alloys and the adherence properties of the mother metal alloys to titanium, additional experiments were conducted. As a result, it has been found that, as the amount of each element contained in the mother metal iron alloy is increased up to a certain limit, the adherence of the alloy to titanium is increased to a certain extent, with a further increase in the amount of the element beyond the limit not appreciably changing the adherence of the alloy of the mother metal. Any excess of the respective alloying elements tends to make the mother metal iron alloy brittle. Therefore, taking into account the adherence, economy and workability, the amounts of molybdenum, vanadium, niobium, zirconium and tungsten should preferably range from 1.0 to 4.0%, from 1.0 to 3.0%, from .5 to 1.5%, from .5 to 1.0% and from 1.0 to 1.5% respectively, on the basis of the total weight of the mother metal alloy.

In practicing the invention when the mother metal is to be bonded to a base plate, a titanium sheet, an intermediate layer of any one of the bonding iron alloys described hereinbefore, and a base plate of suitable metal are superposed upon each other to form a stacked assembly. Then the stacked assembly is heated and hot rolled to produce a composite metallic plate.

In practicing the invention, when the mother metal plate is not to be bonded to a base plate, a titanium sheet is superposed upon a mother metal plate composed of anyone of the iron alloys as hereinbefore described to form a stacked assembly. Then the stacked assembly is heated and rolled to produce a composite metallic plate.

Referring now to FIG. 1 of the drawings, there is illustrated an assembly of a titanium veneer superposed upon a mother metal plate which acts as an intermediate layer of a metallic bonding material according to the invention, and upon a base plate of a dissimilar metal. A titanium sheet, an intermediate mother metal sheet of metallic bonding material, a metal base plate and a cover plate of any suitable material are machined to the desired dimensions respectively. Then those faces of the titanium sheet, the intermediate mother metal sheet of bonding material and the base plate to be attached to each other are mechanically polished and chemically cleaned.

As shown in FIG. 1, the titanium sheet 1 thus treated is put upon the mother metal bonding sheet 2 also preliminarily treated and superposed upon the metal base plate 3 also treated, with the faces of the members which are in contact with each other being in register. Then the cover plate 4 is superposed on the exposed face of the titanium sheet 1 with a parting sheet of any suitable material 5 sandwiched therebetween and with a plurality of spacers of any suitable material 6 interposed between the cover plate 4 and the metal base plate 3 on the marginal portions thereof to form a stacked assembly with the plurality of spacers slightly separated from and surrounding the

sheets

1, 2 and 3. The stacked assembly is made into a unitary structure by having a weld 7 formed along each edge side thereof after a pipe 7 has been suitably disposed between the cover plate 4 and the metal base plate 3 on each of the longitudinal marginal portions as shown in FIG. 1. The pipes 7 serve to evacuate the space between the metal base plate 3, the cover plate 4 and the spacers 6 and also to circulate a flow of inert gas through the space. After the space has been cleaned with the inert gas, the pipes are hermetically cut and a suitable length of each pipe is sealed to the stacked assembly.

The assembly thus formed is then placed into a heating fumnace (not shown) at a temperature of from 800 to 1000 C. for a suitable period of time, for example, a period of time of from 30 to 60 minutes for each inch of the thickness of the assembly. After the lapse of the heating time just described, the heated assembly is removed from the furnace and immediately hot rolled to reduce it from 50 to The temperature of the assembly at the completion of he rolling operation is preferably equal to or higher than 700 C. Then the hot rolled assembly is allowed to cool to room temperature and the cooled assembly is trimmed along its edges and the cover plate is removed from the finished composite plate.

An assembly thus produced was tested and exhibited a shearing strength on the order of from 10 to 30 kgs./ mm. and a workability suitable for various working operations.

In FIG. 2 wherein like reference numerals have been employed to identify the components corresponding to those shown in FIG. 1, there is illustrated a stacked assembly similar to that shown in FIG. 1 excepting that the cover plate 4 is replaced by another stacked assembly portion. Titanium veneers ll, 1' and

mother plates

2, 2 and base plates 3, 3' have been preliminarily treated in the same manner as above described in conjuncti n with FIG. 1 and then a

stacked assembly portion

1, 2, 3 is put in mirror-image relationship upon another stacked

assembly portion

1, 2, 3 with a parting sheet 5 and a plurality of spacers 6 interposed there/between. Then 6 assembly is trimmed along its edges and the cover plate is removed from the finished composite plate.

The composite metallic plates thus produced were tested and exhibited a shearing strength on the order of from 10 the entire assembly can be heated and rolled in the same 5 to 30 kgs./mm and a workability suitable for various manner as above described in conjunction with FIG. 1. working operations. In this case, a pair of the finished composite metallic In FIG. 4, wherein the like reference numerals have plates are produced from each assembly such as shown in been employed to identify the components corresponding FIG. 2. to those shown in FIG. 3 there is illustrated a stacked Referring now to FIG. 3 of the drawings, there is 10 assembly similar to that shown in FIG. 3 excepting that illustrated an assembly of a titanium sheet superposed the cover plate 13 is replace-d by another stacked asupon a mother metal plate composed of an iron alloy sembly portion. Titanium sheets 11, 11' and mother according to the invention without the mother metal metal plates 12, 12' of the invention have been preliminplate being bonded to a base plate. A titanium sheet, arily treated in the same manner as above described in such a mother metal plate and a cover plate of any suitconjunction with FIG. 3 and then a stacked assembly porable material are machined to the desired dimensions tion 11, 12 is put in mirror-image relationship upon anrespectively. Then one face of the titanium sheet and other

stacked assembly portion

11, 12 with a parting one face of the mother plate to be bonded to each other sheet 14 and a plurality of spacers 15 interposed thereare mechanically polished and chemically cleaned. between. Then the entire assembly can be heated and As shown in FIG. 3, the titanium sheet 11 thus treated rolled in the ame manner as above described in conjuncis put upon the mother plate 12 also preliminarily treated tion with FIG. 3. In this case a pair of the finished comwith the treated faces of both members contacting each posite metallic plates are produced from each assembly other and being in register. Then the cover plate 13 is such as shown in FIG. 4. superposed on the exposed face of the titanium sheet 11 To illustrate the results of the invention the shearing with a parting sheet of any suitable material 14 sandstrength and bending properties of various composite wiched there-between and with a plurality of spacers of metallic plates having a bonding layer and produced in any suitable material 15 interposed between the cover accordance with the invention are listed in Table I toplate and the mother plate on the marginal portions theregether with the chemical compositions of the metallic of to form a stacked assembly with the plurality of bonding materials used. The titanium used was a comspacers slightly separated from and surrounding the mercially pure grade and had acomposition including by titanium and parting sheets. The stacked assembly is Weight, 99.5% (min) Ti, 02-08% C, .02-.15% Fe, .02- made into a unitary structure by having a weld 16 formed .10% Si, .0l-.10% 0 100 ppm. (max) H and .001- along each edge side thereof after a pipe 17 has been .10% N while the base plate metal used was ASTM type suitably disposed between the cover plate 13 and the AZOIGB steel including, by weight, .24 (max) C, .15 metal mother plate 12 on each of the longitudinal margi- 30% Si, 80% (.max.) Mn, 035% (max-.) P, 04% nal portions as shown in FIG. 3. The pipes 17 serve (max) S for a-thickness of at most 1 in.

TABLE I Composition of mother metal in percent Thickness of Shearing Bending Specime Base metal plate in mms. Strength, Nu (Titanium kgslmmfl C Si Mn P S Mo V Nb Zr W Mother metal) Inwardly outwardly ASIMA201GB .00 .10 .50 .009 2+12 24.3 Good Good. ASTMA20lGB .04 .22 .43 .010 2+8 20.4 -do Do. ASTMA20lGB .05 .24 .66 .011 2+8 18.1 do Do. ASIM-AZOIGB-.. .08 .18 .51 .011 2+8 17.6 do Do. E ASTM-AZOIGB... .06 .26 .44 .013 2+8 17.1 do Do.

to evacuate the space between the metal mother plate 12, the cover plate 13 and the spacers 15 and also to circulate a flow of inert gas through the space. After the space has been cleaned with the inert gas, the pipes are hermetically cut and a suitable length of each pipe is sealed to the stacked assembly.

The assembly thu formed is then placed into a heating furnace (not shown) at a temperature of from 800 to 1000 C. for a suitable period of time, for example, a period of time of from 30 to 60 minutes for each inch of the thickness of the assembly. After the lapse of the TABLE II Composition of mother metal in percent Thickness of Shearing Bending Specimen plate in mms. Strength, N0. (Titanium-lkgs/rnmfi C Si Mn P S Mo V Nb Zr W Mother metal) Inwardly Outwardly A l0 21 41 018 2+8 B .08 .18 .40 .011 3+13 C 12 20 50 010 2+8 D 10 23 54 011 2+10 E .11 25 .43 .010 2+ heating time just described the heated assembly is removed from the furnace and immediately hot rolled to reduced it firom 50 to 80%. The temperature of the assembly at the completion of the rolling operation is preferably equal to or higher than 700 C. Then the hot rolled assembly From the foregoing, it will be appreciated that the object of the invention has been accomplished by the provision of special iron alloys used as bonding metals and mother plate metals in which the alloying metal is taken from the group consisting of molybdenum, vanais allowed to cool to room temperature and the cooled dium, niobium, zirconium and tungsten.

While the invention has been described in the terms of a composite metallic plate including .a titanium lamination bonded to one face of a mother metal plate or through said mother metal plate to a metal base plate, it is to be understood that a pair of titanium sheets can in the same manner be bonded to both faces of the mother metal plate or through respective intermediate mother metal plates to both sides of a base plate.

What is claimed is:

1. A composite metal plate comprising an iron alloy sheet and a veneer of titanium bonded to at least one face of said iron alloy sheet, said iron alloy sheet consisting essentially of iron and an alloying element taken from the group consisting of molybdenum, vanadium, niobium, zirconium, and tungsten, said element being present in an amount of at least equal to 0.3% by weight of the alloy.

2. A composite metal plate comprising an iron alloy mother plate and a veneer of titanium bonded to at least one face of said mother plate, said iron alloy mother plate consisting essentially of iron and an alloying metal taken from the group consisting of 0.3 to 10.0% by weight of molybdenum, 0.3 to 10.0% by weight of vanadium, 0.3 to 10.0% by weight of niobium, from 0.3 to 6.0% :by weight of zirconium, and from 0.3 to 10.0% by Weight of tungsten.

3. A composite metal plate comprising an iron alloy mother plate and a veneer of titanium bonded to at least one face of said mother plate, said iron alloy mother plate consisting essentially of iron and an alloying metal taken from the group consisting of 1.0 to 4.0% by Weight of molybdenum, 1.0 to 3.0% by weight of vanadium,

0.5 to 1.5% by weight of niobium, 0.5 to 1.0% by weight of zirconium, and 1.0 to 1.5% by weight of tungsten.

4. A composite metal plate comprising a base plate comprising a metal taken from the group consisting of iron and steel, a veneer of titanium adjacent at least one face of said base plate, and a bonding material bonded between said titanium veener and said base plate, said bonding material consisting essentially of iron and an alloying metal taken from the group consisting of 0.3 to 19. 0% by weight molybdenum, 0.3 to 20.0% by Weight vanadium, 0.3 to 15.0% by weight niobium, 0.3 to 8.0% by weight zirconium, and 0.3 to 18.0% by weight tungsten.

5. A composite metal plate comprising a base plate comprising a metal taken from the group consisting of iron and steel, a veneer of titanium adjacent at least one face of said base plate, and a bonding material bonded between said titanium veneer and said base plate, said bonding material consisting essentially of iron and an alloying metal taken from the group consisting of 1.0 to 5.0% by Weight of molybdenum, 1.0 to 5.0% by Weight of vanadium, 0.5 to 2.0% by Weight of niobium, 0.5 to 2.5% by weight of zirconium, and 1.0 to 2.0% by weight of tungsten.

References Cited by the Examiner UNITED STATES PATENTS 2,813,332 11/1957 Keay 29-194 X 2,908,969 10/1959' Wagner 29198 X 2,993,269 7/1961 Kelley 29-498 X HYLAND BIZOT, Primary Examiner.

Claims

0.3 TO 10.0% BY WEIGHT OF NIOBIUM, FROM 0.3 TO 6.0% BY WEIGHT OF ZIRCONIUM, AND FROM 0.3 TO 10.0% BY WEIGHT OF TUNGSTEN.
2. A COMPOSITE METAL PLATE COMPISING AN IRON ALLOY MOTHER PLATE AND A VENEER OF TITANIUM BONDED TO AT LEAST ONE FACE OF SAID MOTHER PLATE, SAID IRON ALLOY MOTHER PLATE CONSISTING ESSENTIALLY OF IRON AND AN ALLOYING METAL TAKEN FROM THE GROUP CONSISTING OF 0.3 TO 10.0% BY WEIGHT OF MOLYBDENUM, 0.3 TO 10.0% BY WEIGHT OF VANADIUM,