CN103415636B - The titanium plate that press formability is excellent - Google Patents

Abstract

The titanium plate of the present invention is in terms of quality %, containing 0.04～the Fe of 0.10%, 0.07～the O of 0.20%, its remainder is Ti and inevitable impurity, in the rolling surface in t/4 (t is thickness of slab) portion, during rolling direction stretching, { area occupation ratio that Schmidt's factor is more than 0.47 of 11-22} ＜ 11-23 ＞ twin crystal deformation is more than 30%, and the graphic memory of the 1mm × 1mm in t/4 (t is thickness of slab) portion whole crystal grain (α phase) in, c-axis is less than 90% relative to the area occupation ratio shared by the crystal grain that angle is 70～90 ° of rolling direction, outside press formability excellence, stretch flanging is the most excellent.

Description

The titanium plate that press formability is excellent

Technical field

The present invention relates to the titanium plate having excellent formability of a kind of punch process etc..

Background technology

Owing to titanium has corrosion resistance and the specific strength of excellence, therefore it is widely used in heat exchanger, change Work bulking block or the structural member etc. in seashore portion, the most completely will not be by seawater corrosion, therefore Relatively it is used for seawater heat exchanger.Wherein, plate type heat exchanger uses the titanium plate being processed into tabular, for Improve heat transfer efficiency and use stamping for the surface titanium plate for concaveconvex shape.Additionally, in recent years In order to improve heat transfer efficiency further, exist make titanium plate thin-walled property, make concaveconvex shape complicate such Demand, there is also the titanium plate that expect the formability such as stamping the most excellent and is developed such back of the body Scape, for the titanium plate that press formability is excellent, proposes the structures such as the material about this titanium plate and it becomes The various schemes of shape process technology.

In terms of the material of titanium, owing to the crystal structure of titanium is hexagonal crystal, therefore have each to different Property, therefore propose as patent documentation 1 and roll in the way of at a right angle with common rolling direction Make, reduce anisotropic method.But, in the method, owing to the midway in manufacturing process must Rolling direction must be changed, therefore exist and have to reduce the such practical situation of productivity ratio.

From the angle of forming technique, suitableization etc. of surface lubrication is studied, such as, Following method is proposed: form the ferrum of lubricant carrier, zinc on the surface of sheet material as patent documentation 2 Alloy-layer, carries out zinc phosphate process afterwards and applies lubricant.But, in the method, in lubrication Agent needs to carry out multiple operation on processing, and is the method for not efficiency for this respect.

Additionally, it is also proposed the scheme of the surface lubrication being much conceived to sheet material, as patent documentation 3 and patent documentation 4 propose titanium plate and the manufacture method thereof being formed with oxide-film at plate surface, make Titanium plate and the manufacture method thereof forming nitrogen-enriched layer on plate surface is proposed for patent documentation 5, as Patent documentation 6 proposes and forms the titanium plate that TiC contains layer on plate surface.But, at these titaniums In plate and manufacture method thereof, need to be formed cover layer on the surface of sheet material, there is its manufacturing process multiple Miscellaneous such practical situation.

Additionally, due to titanium has light weight, corrosion resistance and the aesthetic appearance of excellence, therefore it is also suitable On the component of the carts such as deafener or carriage.In order to be applicable to these components, titanium needs stretching Property, deep drawability, bendability, stretch flanging etc. can with complicated and diversified processing corresponding Shaping processability.

Citation

Patent documentation

Patent documentation 1: Japanese Laid-Open Patent Publication 60-82227 publication

Patent documentation 2: Japanese Laid-Open Patent Publication 63-174749 publication

Patent documentation 3: Japanese Unexamined Patent Publication 6-173083 publication

Patent documentation 4: Japanese Unexamined Patent Publication 6-248404 publication

Patent documentation 5: Japanese Unexamined Patent Publication 10-204609 publication

Patent documentation 6: Japanese Unexamined Patent Publication 2006-291362 publication

Summary of the invention

The problem that invention is to be solved

The present invention makes to solve above-mentioned existing issue, its object is to provide a kind of in punching Outside pressing formation excellence, titanium plate that stretch flanging is also excellent.

For solving the means of problem

Invention described in technical scheme 1 is the titanium plate that a kind of press formability is excellent, and it is in terms of quality %, Containing 0.04～the O of the Fe of 0.10%, 0.07～0.20%, remainder is Ti and inevitable Impurity, it is characterised in that t/4(t is thickness of slab) in the rolling surface in portion, rolling direction stretching time { 11 -22 } area occupation ratio that Schmidt's factor is more than 0.47 of ＜ 11-23 ＞ twin crystal deformation is more than 30%, T/4(t is thickness of slab) graphic memory of the 1mm × 1mm in portion whole crystal grain (α phase) in, c-axis It is less than 90% relative to the area occupation ratio shared by the crystal grain that angle is 70～90 ° of rolling direction.

Invention described in technical scheme 2 is the titanium excellent according to the press formability described in technical scheme 1 Plate, it is characterised in that be thickness of slab at t/4(t) portion 1mm × 1mm graphic memory crystal grain (α Phase) average crystal grain diameter be 20～200 μm.

Invention effect

The titanium plate that press formability is excellent can be obtained according to the present invention.Additionally, in the excellence of titanium itself On the basis of durability, add higher mechanical strength, there is press formability and the excellence of excellence Stretch flanging, therefore outside the structural member of plate type heat exchanger, additionally it is possible to be widely used in two and take turns Car carriage component, the dividing plate of fuel cell, mobile phone, notebook computer, the machine of digital camera Body, spectacle-frame etc. heavily stressed and require height formability purposes.

Additionally, by the average crystal grain diameter suitably controlling crystal grain (α phase), it is possible to it is set to guaranteeing Outside excellent press formability and the excellent titanium plate of stretch flanging.

Accompanying drawing explanation

Fig. 1 be for illustrate the c-axis angle relative to rolling direction with reference to figure.

Fig. 2 represents in an embodiment for evaluating the press forming die of press formability and outward appearance, figure (a) of 2 is top view, and (b) of Fig. 2 is the F-F sectional view of Fig. 2 (a).

Detailed description of the invention

The present inventor, in order to obtain the titanium plate that press formability is excellent and stretch flanging is also excellent, enters Go wholwe-hearted experimentation.As a result of which it is, present inventor have discovered that by the amount in regulation Fe Outside the amount of O, suitably controlling this titanium plate t/4(t is thickness of slab) rolling in the rolling surface in portion Schmidt's factor of { 11-22 } ＜ 11-23 ＞ twin crystal deformation during stretching of direction processed is more than 0.47 Area occupation ratio, and the t/4(t to titanium plate is thickness of slab) exist in the plane 1mm × 1mm in portion In crystal grain (α phase), c-axis is relative to the face shared by the crystal grain that angle is 70～90 ° of rolling direction Long-pending rate suitably controls such that it is able to obtain press formability excellence and stretch flanging is the most excellent Titanium plate, thus complete the present invention.

Hereinafter, based on embodiment, the present invention is described in detail.

Portion in the present invention, it is stipulated that the one-tenth of titanium plate is grouped into, the t/4(t of this titanium plate is thickness of slab) Rolling surface in rolling direction stretching time { 11-22 } ＜ 11-23 ＞ twin crystal deformation Schmidt because of Son is the area occupation ratio of more than 0.47 and is thickness of slab at the t/4(t of titanium plate) the plane 1mm × 1mm in portion In the crystal grain (α phase) of interior existence, c-axis is relative to the crystal grain that angle is 70～90 ° of rolling direction Shared area occupation ratio, is first grouped into one-tenth and illustrates.

(one-tenth is grouped into)

Pure titanium trace contains the inevitably impurity such as C, H, O, N, Fe, in the present invention, rule Determine that wherein amount is more, the amount of Fe and O that be that impact engineering properties.

When the amount of Fe becomes too much more than 0.10 mass %, exist stress become excessive, The tendency that press formability and stretch flanging decline.Thus, the upper limit of Fe amount is 0.10 matter Amount %.The preferred upper limit that it should be noted that Fe amount is 0.08 mass %, is more highly preferred to The upper limit is 0.06 mass %.On the other hand, when Fe amount is less than 0.04 mass %, stress Can become too small, therefore the lower limit of Fe amount is 0.04 mass %.

When O amount becomes too much more than 0.20 mass %, there is stress and become excessive, punching The tendency that pressing formation and stretch flanging decline.Thus, the upper limit of O amount is 0.20 mass %. The preferred upper limit that it should be noted that O amount is 0.16 mass %, and the upper limit being more highly preferred to is 0.12 mass %.On the other hand, when O amount becomes less than 0.07 mass %, stress can become Obtaining too small, therefore the lower limit of O amount is 0.07 mass %.

Additionally, the t/4(t for titanium plate is thickness of slab) rolling direction stretching in the rolling surface in portion time { 11-22 } ＜ 11-23 ＞ twin crystal deformation the area occupation ratio that Schmidt's factor is more than 0.47 and It is thickness of slab at the t/4(t of titanium plate) in the crystal grain (α phase) that exists in the plane 1mm × 1mm in portion , c-axis is relative to the regulation reason of the area occupation ratio shared by the crystal grain that angle is 70～90 ° of rolling direction As described below.

(during rolling direction stretching, Schmidt's factor of { 11-22 } ＜ 11-23 ＞ twin crystal deformation is 0.47 Above area occupation ratio)

When the t/4(t of titanium plate is thickness of slab) in the rolling surface in portion, rolling direction stretching time { 11- 22 } face that Schmidt's factor (Schmid Factor) is more than 0.47 of ＜ 11-23 ＞ twin crystal deformation When long-pending rate is too small, the frequency of the secondary twinning produced when titanium plate shapes becomes too small, it is impossible to obtain this The bright excellent press formability intentionally got.In order to ensure it is within the contemplation of the invention that the excellent punching press that obtains Formability, the face that Schmidt's factor is more than 0.47 in { 11-22 } face during stretching of described rolling direction Long-pending rate is necessary for more than 30%.Preferably, Schmidt's factor be the area occupation ratio of more than 0.47 be 35% Above, it is further preferred that the area occupation ratio that Schmidt's factor is more than 0.47 is more than 40%.

(c-axis is relative to the area occupation ratio shared by the crystal grain that angle is 70～90 ° of rolling direction)

When the t/4(t of titanium plate is thickness of slab) graphic memory of the 1mm × 1mm in portion whole crystal grain C-axis shown in (α phase), Fig. 1 is 70～90 ° relative to the angle (θ) of rolling direction When area occupation ratio shared by crystal grain becomes excessive, the anisotropy of material can become excessive, with each to same Property deformation stretch flanging decline, it is impossible to obtain stretch flanging desired by the present invention.For terrible To the stretch flanging desired by the present invention, described c-axis is 70～90 ° relative to the angle of rolling direction The area occupation ratio shared by crystal grain be necessary for less than 90%.Preferably, its area occupation ratio is less than 85%, It is further preferred that its area occupation ratio is less than 80%.

(average crystal grain diameter of crystal grain)

It is above in the present invention the necessary important document of regulation, by the most suitably controlling the t/4 of titanium plate The graphic memory of the 1mm × 1mm in (t is thickness of slab) portion the average crystal grain of crystal grain (α phase) straight Footpath, outside the press formability guaranteeing excellence, and can obtain the titanium plate that stretch flanging is excellent.

When the t/4(t of titanium plate is thickness of slab) graphic memory of the 1mm × 1mm in portion crystal grain (α Phase) average crystal grain diameter when becoming excessive, stamping after the rough surface of titanium plate become notable, Expection is not reached in appearance as stamping product.Thus, by the average crystal grain of crystal grain (α phase) Diameter is set to below 200 μm.The preferred upper limit of the average crystal grain diameter of crystal grain (α phase) is 150 μm, the further preferred upper limit is 100 μm.On the other hand, when average crystal grain diameter is too small, The frequency of the secondary twinning produced when titanium plate shapes can become too low, it is difficult to guarantees sufficient ductility, The excellent press formability desired by the present invention cannot be obtained.Thus, putting down crystal grain (α phase) All crystal grain diameters are set to more than 20 μm.The average crystal grain diameter of crystal grain (α phase) preferred under Being limited to 35 μm, further preferred lower limit is 50 μm.

(manufacturing condition)

It follows that the manufacture method of titanium plate of the present invention is illustrated.Common titanium plate is by cutting Divide the such each inter process of rolling → hot rolling → intermediate annealing → cold rolling → final annealing, rouse at any time Wind, pickling processes make, but are grouped into according to the one-tenth of titanium plate manufactured, the setting of each operation Condition and the physical property, the structural state that obtain can change, therefore should be as a series of system Making operation and come comprehensive selection, decision condition, the way imposed a condition closely in each operation is not Must be appropriate.

But, the manufacturing condition of the titanium plate for manufacturing the present invention has been carried out grinding with keen determination by the present inventor Study carefully, be identified through using manufacturing condition shown below, it is possible to reliably produce institute of the present invention Desired press formability and the titanium plate of stretch flanging excellence.

Its manufacturing condition is: splitting rolling, hot rolling, cold rolling all carry out in the same direction, and Each reduction ratio of splitting rolling is more than 5%, and final cold rolling rate is more than 70%, final annealing Temperature is 500～810 DEG C, and the retention time of final annealing is less than 1 hour.By appropriately combined this A little conditions manufacture titanium plate, it is possible to produce the press formability desired by the present invention and stretch flanging Excellent titanium plate.

Embodiment

Hereinafter, enumerate embodiment and further illustrate the present invention, certainly, the invention is not limited in Following embodiment, can also add suitably change meeting and implement in the range of present subject matter, this All it is contained within the technical scope of the present invention a bit.

In the present embodiment, CCIM(cold-crucible induction melting is first passed through) cast out and pass through Amount shown in table 1 carrys out the titanium ingot casting containing Fe and O.Remainder is Ti and C, H, The inevitably impurity such as N.The size of ingot casting is the cylinder of φ 100mm, weight 10kg.Use This ingot casting and carry out splitting rolling according to each reduction ratio shown in table 1, carry out afterwards letting cool and obtaining Splitting rolling material to the tabular that thickness is 45mm.Further, implement hot rolling, carry out de-scaling and Obtain the hot rolled plate that thickness is about 5mm.

It follows that in atmospheric furnace, heat the annealing that laggard circulation of qi promoting in 5 minutes is cold at 700 DEG C (intermediate annealing), carries out de-scaling afterwards.Then, according to the cold rolling rate shown in table 1 carry out cold rolling it After, in vacuum annealing furnace, after heating according to condition shown in table 1, carry out the annealing of air cooling (final annealing), then, implements skin-pass, carries out de-scaling and produce the titanium of thickness 0.5mm Plate.

In the present embodiment, the observation of metal structure etc., mensuration and the stress of each titanium plate produced And the evaluation of press formability is carried out according to following main points respectively.

In the present embodiment, by electric field radioactive scanning microscope (Field Emission Scanning Electron Microscope:FESEM) on (NEC society system, JSM5410) Carry electron backscattered pattern (Electron Back Scattering(Scattered) Pattern:EBSP) The crystal orientation analytic method of system implements the observation of metal structure, mensuration.Use this assay method Reason is, EBSP method has high de-agglomeration energy compared with other assay methods, it is possible to carry out high accuracy Mensuration.First, measuring principle is illustrated.

EBSP method is the sample irradiation electron beam arranged in the lens barrel of FESEM, on a display screen Projection EBSP.Utilize high sensitivity photographing unit that it is shot, input computer in the form of images. Resolve this image, by comparing, certainly with using pattern produced by the simulation experiment of known crystallographic system The orientation of fixed crystallization.The orientation of the crystallization calculated is set to three-dimensional Eulerian angles, with position coordinates (X, Etc. Y) jointly record.This process is carried out automatically relative to all measuring points, is measuring knot Shu Shineng accesses tens thousand of～hundreds thousand of points.

So, with X-ray diffraction method or the electron beam diffraction method phase of use transmission electron microscope Ratio, EBSP method has an advantage that field of view is wider, it is possible to obtain relatively within a few hours Various information in most crystal grain of more than hundreds of.Additionally, because being not to measure each crystal grain, But the region that sweep measuring is specified at certain intervals, the most also have and be obtained in that and enlist the services of whole survey Determine above-mentioned multiple measuring points in region relevant, the advantage of above-mentioned each information.It addition, at these FESEM The detailed content of the crystal orientation analytic method of upper lift-launch EBSP system is recorded in Kobe system in detail Steel skill report/Vol.52No.2(Sep.2002) P66-70 etc..

(during rolling direction stretching, Schmidt's factor of { 11-22 } ＜ 11-23 ＞ twin crystal deformation is 0.47 Above area occupation ratio, c-axis are relative to the area shared by the crystal grain that angle is 70～90 ° of rolling direction Rate)

The rolling surface surface of titanium plate is carried out mechanical lapping, carries out electrobrightening the most after polishing, It is adjusted, enabling degree of depth t/4(t observing distance titanium plate surface is thickness of slab) the rolling of portion The crystal structure in face processed (face parallel with titanium plate surface, the face in the degree of depth t/4 portion in its thickness of slab direction), { 11-22 } ＜ 11-23 ＞ when the rolling direction in its rolling surface stretches is obtained by said determination The area occupation ratio that Schmidt's factor is more than 0.47 of twin crystal deformation and c-axis are relative to rolling direction Angle is the area occupation ratio shared by the crystal grain of 70～90 °.Measure in the plane that region is 1mm × 1mm, Measuring frequency is 1 μm.

The quantity utilizing the measuring point that Schmidt's factor is more than 0.47 of each measuring point determined is removed When calculating rolling direction stretching with the quantity of all measuring points, { 11-22 } ＜ 11-23 ＞ twin crystal becomes The area occupation ratio that Schmidt's factor is more than 0.47 of shape.

By the quantity that angle is 70～90 ° of the c-axis of each measuring point that determines divided by all mensuration Point quantity and calculate c-axis relative to the area shared by the crystal grain that angle is 70～90 ° of rolling direction Rate.

The average crystal grain diameter ＞ of ＜ crystal grain (α phase)

The average crystal grain diameter of crystal grain (α phase) is tried to achieve as follows: roll titanium plate Surface, face processed carries out mechanical lapping, is etched the most after polishing, is adjusted making it possible to see Observe the crystal structure of the rolling surface in the degree of depth t/4 portion on distance titanium plate surface, use optical microscope to exist In the case of × 100, position at any three is carried out photograph taking, pass through based on the photo obtained The patterning method of JIS G0551 is implemented granularity number and is measured, based on this granularity number, by meter Calculate and obtain equivalent circle mean diameter (diameter) of α phase.It should be noted that granularity number measures The viewing area of the optical microscope of middle use is 1mm × 1mm.

＜ stress determination ＞

The stress of titanium plate is tried to achieve as follows: made by each titanium plate produced No. 13 test specimens of JISZ2201 defined, for this test specimen, carry out the stretching examination according to JISZ2241 Test, and then measure the test specimen 0.2% stress (YS) in rolling direction.It addition, by test specimen with it longitudinally Direction (L direction) mode consistent with rolling direction is taked.Additionally, test speed (is drawn Stretch the rate of straining in test) be set to 0.3mm/min constant.

By the test specimen obtained by this test 0.2% stress (YS) of rolling direction be 200MPa with On situation, be evaluated as heavily stressed.

＜ press formability ＞

For press formability, change as in figure 2 it is shown, use to simulate being provided with the board-like of V-shaped groove The heat exchanging part of hot device carries out stamping press forming die to implement the punching press of titanium plate (test specimen) Shape, carry out it and evaluate.Press forming die is as in figure 2 it is shown, the size of forming section is 100mm × 100mm, in its surface, formed six stripe pitch be 10mm, maximum height be 4mm The parallel ridge line section of vertical view V-shaped.Upper from (a) of Fig. 2 of the R shape of this each ridge line section Side is followed successively by downward R=0.4,1.8,0.8,1.0,1.4,0.6 and adds up to six kinds.

Use this shaping dies, implement stamping by 80ton oil pressure stamping machine.Specifically, Applying dynamic viscosity on the inside and outside face of each test specimen is 34mm²/ s(40 DEG C) punching oil, will be each Test specimen is configured in the way of its rolling direction (L direction) is consistent with the above-below direction of (a) of Fig. 2 The upper surface of lower mold, after limiting its flange part by pressing plate, drawing velocity be 1mm/s, Compression distance be implement under conditions of 3.4mm stamping.For the evaluation of press formability, pass through The quantity of the fracture confirmed after stamping is evaluated.The evaluation methodology that following description is concrete.

For the ridge line section shown in (a) of Fig. 2 of each test specimen after stamping and the A that locates, B, The intersection point of the dotted line of C, C ', D, E amounts at 36, and whether visualization has fracture.Need explanation , the C ' that locates, as shown in (b) of Fig. 2, is in the valley between adjacent ridge line section.

In visualization, locate A, C, C ', E for becoming break origins, if assert It not to rupture and attenuate, be denoted as 2 points, if assert is to attenuate, be denoted as 1 point, if assert is to rupture, It is denoted as 0 point, for other locate B, D, if assert is not to rupture and attenuate, is denoted as 1 Point, if assert is to attenuate, it is denoted as 0.5 point, if assert is to rupture, is denoted as 0 point, further at this Be multiplied by each mark processing R inverse and will fracture status number value, obtain its aggregate value.To recognize Fixed entirely without fracture, situation about attenuating be set to 100 be standardized after, will rely on temperature (T), Oil body (μ), function F(T, the μ of thickness of slab (t) of test specimen, t) and rely on punching press The angle (α) of mould crest line, the function G(α of frequency (p), p) be multiplied, obtain as formability Divide and calculate this aggregate value.It should be noted that F and G is between 0～1.

The computational methods of above formability score can be indicated by following formula.

Formability score=F × G × Σ E(ij)/R(j)/(Σ A, C, C ', E2/R(j) + Σ B, D1/R(j)) × 100

In the formula, in the case of A, C, C ', E, E(ij)=1.0 × (without rupturing and attenuating: 2, attenuate: 1, fracture 0)；In the case of B, D, E(ij)=0.5 × (without rupturing and attenuating: 2, attenuate: 1, fracture 0).Additionally, in the present embodiment, due to temperature (T), lubricating oil Viscosity (μ), the thickness of slab (t) of test specimen, the angle (α) of diel crest line and diel rib The spacing (p) of line is constant, calculates formability score in order to F × G is set to convenience of calculation 1.

By this formability score calculated situation more than 50 points, it is evaluated as press formability excellent. It should be noted that in Table 1, formability score situation ◎ more than 75 points is represented, By 50 points～represent with zero less than the situation of 75 points, by × the expression of the situation less than 50 points.

＜ stretch flanging ＞

For the stretch flanging of titanium plate, try to achieve in the following way: from each titanium plate cutting produced Go out the blank plate of 70 × 70 × 0.5mm size, form φ 10 at this blank plate centrally through punching Hole, afterwards, is arranged on stand in the way of its burr formation produced in time making punching onboard side, Push 60 ° of circular cone puncheres from lower section upward and carry out hole expansion test.

In test, pushing away of puncher is stopped rapidly when being visually confirmed to be the generation crack, edge in hole Pressure, the diameter in the hole inscribed when measuring this, afterwards, by (diameter of test metapore)/(test The diameter in front hole) such formula calculates hole expansibility λ (%).Hole expansibility λ that this is calculated It is the situation of more than 90%, is evaluated as stretch flanging excellent.

＜ rough surface ＞

By the evaluation of above-mentioned press formability, in each test specimen, after stamping, assert do not have The V-shaped apex of fracture, is visually confirmed to be shaggy state.By this confirmation, in V-shaped At apex, by entirely without assert shaggy situation be set to zero, identification is had the most concavo-convex Situation is set to ×, the outward appearance also with excellence it is evaluated as after stamping by zero.

Above result of the test is shown in Table 1 below.

[table 1]

No.1 be Fe amount be the titanium plate of lower limit 0.04 mass %, No.2 be Fe amount be upper Limit the titanium plate of 0.10 mass %, additionally, No.3 is O amount is the titanium plate of the upper limit 0.20 mass %, No.4 is each reduction ratio titanium plate close to lower limit of splitting rolling, and No.5 is each of splitting rolling Reduction ratio is up to the titanium plate of 9.2%, and No.6 is cold rolling the coldest to prolong the rate titanium plate (O close to the upper limit Amount also close to lower limit), No.7 is the cold rolling titanium plate that the coldest rate of prolonging is lower limit 70%.On The one-tenth stating No.1～7 is grouped into the important document being satisfied by the present invention, and its manufacturing condition is also preferred condition.

In contrast, No.8 is the titanium plate that Fe amount exceedes the upper limit, and No.9 is that O amount exceedes The titanium plate of the upper limit, No.10 is each reduction ratio titanium plate less than lower limit of splitting rolling, and No.11 is The coldest cold rolling rate of prolonging is less than the titanium plate of lower limit, and No.12 is that the average crystal grain of crystal grain (α phase) is straight Footpath is more than the titanium plate of the upper limit, and No.13 is the titanium plate that the amount of Fe Yu O is below lower limit.

When No.1～7 is satisfied by rolling direction stretching, the deformation of { 11-22 } ＜ 11-23 ＞ twin crystal executes The close special factor be more than 0.47 area occupation ratio, c-axis be 70～90 ° relative to the angle of rolling direction The such important document given to this invention of area occupation ratio shared by crystal grain.As a result of which it is, 0.2% stress (YS) All at more than 200MPa, the result of the test of press formability is also zero or ◎, and hole expansibility (turn over by stretching Limit property) also it is more than 90%.It is to say, the titanium plate of No.1～7 is heavily stressed and strike out Outside shape excellence, titanium plate that stretch flanging is also excellent.

On the other hand, No.9～11,13 formation 0.2% stress (YS), press formability, reaming Any one above result being all unsatisfactory for qualification determination standard in rate.Additionally, No.12 forms c-axis phase Area occupation ratio shared by the crystal grain that angle is 70～90 ° of rolling direction is exceeded to the result of the upper limit, V-shaped apex is identified rough surface.That is, the titanium plate of important document given to this invention it is unsatisfactory for, Can not be said to be outside heavily stressed and press formability is excellent, the titanium plate that stretch flanging is also excellent.

Above, in detail and describe the present invention with reference to specific embodiment, but for this For skilled person, it is possible to add in the case of without departing from the technological thought of the present invention and scope Various changes or amendment are self-evident.

The application is based on Japanese patent application (Patent 2011-filed in 1 day April in 2011 082065) complete, its content is described herein by reference and writes into.

Industrial applicibility

The titanium plate of the present invention can be widely applied for heat exchanger, chemical equipment component or the knot in seashore portion Components etc., particularly therefore it will not be useful as seawater heat exchanger by seawater corrosion.Additionally, Can also be applied to the component of the carts such as deafener four wheel, the dividing plate of fuel cell, mobile phone, Notebook computer, the body of digital camera, spectacle-frame etc. heavily stressed and require height formability use On the way.

Claims (2)

1. press formability is an excellent titanium plate, it is in terms of quality %, containing 0.04～0.10% The O of Fe, 0.07～0.20%, remainder is Ti and inevitable impurity, it is characterised in that

When in the rolling surface in t/4 portion, rolling direction stretches, { 11-22} ＜ 11-23 ＞ twin crystal deforms Schmidt's factor be the area occupation ratio of more than 0.47 more than 30%, and

The graphic memory of the 1mm × 1mm in t/4 portion whole crystal grain in, c-axis is relative to rolling side To the crystal grain that angle is 70～90 ° shared by area occupation ratio be less than 90%,

T is thickness of slab, and described whole crystal grain are whole crystal grain of α phase.

The titanium plate that press formability the most according to claim 1 is excellent, it is characterised in that

The graphic memory of the 1mm × 1mm in t/4 portion the average crystal grain diameter of crystal grain be 20～ 200 μm,

T is thickness of slab, and described crystal grain is the crystal grain of α phase.