|European Case Law Identifier:||ECLI:EP:BA:2013:T013711.20130415|
|Date of decision:||15 April 2013|
|Case number:||T 0137/11|
|IPC class:||C22C 14/00
|Language of proceedings:||EN|
|Download and more information:||
|Title of application:||Article having a dispersion of ultrafine titanium boride particles in a titanium-base matrix|
|Applicant name:||GENERAL ELECTRIC COMPANY|
|Relevant legal provisions:||
|Keywords:||Main request: novelty of claim 1 (yes) - after amendment|
Summary of Facts and Submissions
I. In its decision posted on 2 July 2010 the examining division refused European application No. 05 256 818.5.
The examining division found that the subject matter of claim 1 then on file was anticipated by the technical disclosure of either document
D1: EP-A-1 101 831 or
D3: EP-A-0 751 228
and therefore lacked novelty.
II. The appellant (applicant) lodged an appeal against this decision. The appeal was received at the European Patent Office on 7 September 2010 and the appeal fee was paid on the same date.
The statement setting out the grounds of appeal was received on 12 November 2010. Enclosed therewith, the appellant submitted a primary request and first to fourth auxiliary requests.
In response to the official communication annexed to the summons for oral proceedings, wherein the Board gave its provisional view on the case, and in a further response to a telephone conversation with the rapporteur, the appellant requested that prosecution of the application be proceeded with on the basis of the claims of the fourth auxiliary request submitted on 11 April 2013. Should the Board be minded to remit the application to the department of first instance for further prosecution, the primary and first to third auxiliary requests submitted on 12 November 2010 were withdrawn.
Oral proceedings were requested, should a negative decision be contemplated by the Board.
III. Independent claim 1 of the fourth auxiliary request, now main request, reads as follows:
"An article (20) comprising a microscale composite material (21) having a titanium-base composition matrix (22) comprising more titanium by weight than any other element;
a dispersion of titanium boride particles (24, 25) in the titanium-base composition matrix (22), characterised in that at least 50 volume percent of the intragranular titanium boride particles (24) have a maximum dimension of less than 2 micrometers; wherein:
boron is present at a level in excess of its room temperature solid solubility in the titanium-base composition, up to a level required to form no more than 90 percent by volume titanium boride, and wherein: the titanium-base composition matrix (24) is polycrystalline; and wherein:
the intragranular titanium boride particles (24) within each grain (30) are coherent or partially coherent with the titanium-base composition matrix (22) of said grain (30)."
Dependent claims 2 to 12 relate to preferred embodiments of the article set out in claim 1.
IV. The appellant's arguments are summarized as follows:
The subject matter of claim 1 of the main request resulted from a combination of claims 1 and 6 as originally filed. Neither D1 nor D3 disclosed the subject matter set out in independent claim 1 including the feature that the titanium-base composition was polycrystalline and wherein the intragranular titanium boride articles within each grain were coherent or partially coherent with the titanium-base composition matrix of said grain.
The subject matter of claim 1 of the main request was therefore novel.
Reasons for the Decision
1. The appeal is admissible.
2. Amendments; Article 123(2) EPC
The subject-matter of amended claim 1 of the main request results from a combination of originally filed claims 1 and 6 and the technical information given on page 4, last paragraph to page 5, first paragraph of the application as filed.
Dependent claims 2 to 8 correspond to originally filed claims 2 to 4, 7, 8 and 10, respectively, and dependent claims 9 to 11 have a basis in the technical details given on page 3, last paragraph of the application as originally filed. Claim 12 finds support on page 12, last paragraph of the application as filed.
Hence, there are no formal objections to the claims with respect to Article 123(2) EPC.
3. Interpretation of claim 1
Claim 1 of the main request relates to a composite material comprising:
(a) a polycrystalline titanium-base composition matrix (Ti > 50 wt %);
(b) boron in excess of its room temperature solid solubility in the Ti-base composition matrix up to a level to form not more than 90 vol% Ti-boride dispersed in the matrix;
(c) with >= 50 vol% of the intragranular titanium boride particles (24) being < 2 mym in size and wherein
(d) the intragranular titanium boride particles (24) within each grain (30) are coherent or partially coherent with the titanium-base composition matrix (22) of said grain.
4. Novelty; Article 54(2) EPC
4.1 Document D1 is concerned with a powder-metallurgically produced composite material consisting of a Ti-base matrix (Ti > 50 wt %) and a particle element powder dispersed in the matrix (D1, claim 1). The particle element powder, an example of which is titanium boride having TiB2 as a major component, exhibits an average particle diameter ranging from 0.5 to 50 mym or, more preferably, from 0.5 or 1 to 30 mym (D1, claim 15; paragraphs , , , ). It is evident from the examples given in D1, Tables 1 and 2 that the TiB2 particles in the matrix are present in amounts between 1 to 10 vol% (Table 1) or 5 to 15 vol% (Table 2), respectively. The process of producing the known Ti-base composite material comprises the steps of mixing a prepared Ti-powder, alloying element powder and particle element powder, forming a green compact e.g. by cold isostatic pressing and sintering the compact at the beta transformation temperature or above. The final composite is, therefore, expected to exhibit a polycrystalline structure wherein the titanium boride particles are uniformly dispersed (D1, paragraphs  to ; , ).
However, the article known from document D1 is not disclosed to exhibit feature (d) of the claimed composite article which requires that the intragranular titanium boride particles within each grain are coherent or partially coherent with the titanium-base composition matrix of said grain.
4.2 Document D3 discloses a TiAl master alloy consisting of a 50-53at% Ti - 47-50at% Al intermetallic compound (50at% Ti - 50at% Al ? 61,5wt% Ti-38.5 wt% Al matrix composition) which comprises fine Al2O3- and TiB2-particles dispersed therein (D3, claim 3). The TiB2-particles are specified to result in a boron concentration of 0.1 to 10 at% and the diameter of the TiB2 particle is specified to be not more than 500 nm (0.5 mym), (D3, claim 3; page 2, lines 53 to 57). It is evident from D3, examples 3 to 5 that, by using the twin-roll direct casting process for casting the TiAl-master alloy with 1 at% TiB2 dispersed therein, a Ti-base composition matrix having a grain diameter of 20 mym or even 10 mym is achieved (D3, page 6, lines 43 to 45, page 8, lines 56 to page 9, line 2; page 9, lines 56 to 59). However, document D3 also fails to disclose feature (d) of claim 1 of the main request.
4.3 For these reasons, the Board concludes that the article set out in claim 1 of the main request is novel vis-à-vis the technical disclosure of documents D1 or D3, respectively, in accordance with Article 54(2) EPC.
The same reasoning applies to the remaining claims 2 to 12 in view of their dependency on claim 1.
Given that the ground of lack of novelty relied on in the decision of the examining division for refusing the application no longer applies, the decision under appeal must be set aside.
The examining division has not yet examined whether the application as amended meets the requirement of inventive step pursuant to Article 56 EPC. The Board, in accordance with the appellant's request, finds it appropriate therefore to remit the case to the department of first instance for further prosecution.
6. Since the request for oral proceedings was conditional on the intention of the Board to issue a negative decision, which condition is not met, no oral proceedings are necessary.
For these reasons it is decided that:
1. The decision under appeal is set aside.
2. The case is remitted to the department of first instance for further prosecution.