Exhibit 5.1



                                 May 18, 2001


Allegheny Technologies Incorporated
1000 Six PPG Place
Pittsburgh, PA  15222-5479

Ladies and Gentlemen:

         I am, Counsel,  Corporate and General Business and Assistant  Secretary
of  Allegheny  Technologies  Incorporated  (the  "Company")  and I have acted as
counsel for the Company in connection with the  preparation of the  Registration
Statement  on Form S-8 to be  filed  by the  Company  with  the  Securities  and
Exchange  Commission for the  registration  under the Securities Act of 1933, as
amended,  of 100,000  shares of the Company's  common stock,  par value $.10 per
share  (the  "Shares"),  which  are to be issued  from  time to time to  certain
employees  of the  Company  and  its  affiliates  in  connection  with  the  TDY
Industries,  Inc.  Profit  Sharing Plan for Certain  Employees  of  Metalworking
Products (the "Plan").

         I have examined the  originals,  certified  copies or copies  otherwise
identified  to my  satisfaction  as being true copies of the Plan and such other
documents  as I have  deemed  necessary  or  appropriate  for  purposes  of this
opinion.

         Based on the  foregoing,  I am of the opinion that the Shares have been
duly and validly authorized and reserved for issuance, and that the Shares, when
issued under the terms of the Plan,  will be legally and validly  issued,  fully
paid and nonassessable.

         I hereby  consent to the filing of this  opinion as Exhibit  5.1 to the
Registration Statement.

                                          Very truly yours,


                                          /s/ Scott E. Westwood
                                          --------------------------
                                          Scott E. Westwood