UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): May 15, 2013

AGY HOLDING CORP.

(Exact name of registrant as specified in its charter)

(888) 434-0945

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

On May 15, 2013, AGY Holding Corp. (“AGY”) announced via press release its financial results for the first quarter ended March 31, 2013 and that it will hold a teleconference to discuss those results on Friday, May 17, 2013. A copy of the press release is attached hereto as Exhibit 99.1.

The information in Item 2.02. of this Form 8-K and the Exhibit attached hereto shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

Certain statements contained in this Current Report on Form 8-K are forward-looking and involve risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such forward-looking statements. All statements included herein, other than statements of historical fact, may constitute forward-looking statements. In some cases you can identify forward-looking statements by terminology such as “may,” “should” or “could.” Generally, the words “anticipates,” “believes,” “expects,” “intends,” “estimates,” “projects,” “plans” and similar expressions identify forward-looking statements. Although AGY believes that the expectations reflected in such forward-looking statements are reasonable, it can give no assurance that such expectations will prove to be correct. Among these risks and uncertainties are general economic and business conditions; our ability to complete the debt restructuring on the terms described, or at all; AGY’s substantial debt and ability to generate cash flows to service its debt; AGY’s compliance with the restrictive covenants contained in its various debt agreements; adverse changes in market conditions or product demand; the level of cost reduction achieved through restructuring and capital expenditure programs; changes in energy, alloy metals and raw material costs and availability; downward selling price movements; the success of new technology; labor disputes or increased labor costs; AGY US’s borrowing base sensitivity to precious metals market prices and amount of owned alloy metals; AGY US’s ability to maintain an available minimum $6.25 million borrowing capacity to avoid the triggering of a springing covenant, which would likely result in an event of default under its senior secured revolving facility; AGY’s ability to complete a divestiture or alternative exit event on acceptable terms and in a timely manner; currency and interest rate fluctuations; increases in AGY’s leverage; AGY Asia’s ability to satisfy its mandatory term loan repayment obligations, to refinance its working capital loan, and to get a waiver for the breach of the maximum debt-to-assets ratio covenant; changes in AGY’s business strategy or development plans; the timing and cost of plant closures; and increases in the cost of compliance with laws and regulations. Additional factors that could cause actual results to differ materially from these forward-looking statements include, but are not limited to, those risk factors listed from time to time in AGY’s filings with the Securities and Exchange Commission. Except as required by applicable law, AGY assumes no obligation and does not intend to update these forward-looking statements.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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