Mohasco Corp., the nation's largest interior furnishings company, is applying for industrial revenue bonds to finance moving its corporate headquarters to Fair Lakes office park in western Fairfax County.

If the company does move from Amsterdam, N.Y., it will become the first Fortune 500 company with corporate headquarters in Fairfax County and the 42nd with offices there.

Mohasco, best known for its Mohawk carpets, also would become the second nationally prominent corporation at Fair Lakes, Hazel/Peterson Cos.' office and residential park under construction near the junction of Interstate 66 and Route 50. TRW Inc.'s Defense Systems Group has purchased land for a regional marketing center at Fair Lakes. Planners say the area is one of the most rapidly growing in Fairfax County.

But Mohasco is battling a hostile takeover bid and, in the meantime, wants no publicity on the proposed move from the Albany, N.Y., area, according to an internal memo at the Fairfax County Economic Development Authority.

Mohasco Vice President Charles Egan declined to comment on the company's application to the authority for $7 million worth of tax-exempt bonds. The application says the headquarters would employ 149 people and contribute $105,800 annually to the county's tax base.

According to reports in The Wall Street Journal, four Florida-based real estate investors and a New York investment firm, Columbia Enterprises, have offered to buy Mohasco for $32 a share; its board has responded by filing suit, claiming that the bidders are manipulating stock value and that the offer is insufficient. In its 1984 annual report, Mohasco put its book value as equal to $32.59 a share.

The application for tax-free financing also states that Mohasco proposes to construct a 60,000-square-foot office building on five acres of land it is considering buying for $1.5 million from Hazel/Peterson.

If the plan proceeds, Hazel/Peterson would have to seek an amendment to its conceptual development plan for Fair Lakes.

The land Mohasco may purchase is planned for residential use and abuts the Cedar Lake Estates subdivision. The residents there, however, are applying to have the neighborhood replanned from residential to commercial use. If this amendment to the comprehensive plan succeeds, it is unlikely that local residents will oppose the Mohasco location, said Tony Hadley, an aide to Supervisor James M. Scott, who represents the Fair Lakes area.

The comprehensive plan guides future planning decisions in the county. The staff is reviewing 12 amendments to the plan for the area around the intersection of Interstate 66 and Route 50, and the board is not expected to vote on the application until the end of the year, planner Barbara Byron said.

So long as Hazel/Peterson provides the residential development elsewhere on its 620-acre site, Scott said he has no objection to the company changing the conceptual development plan. To date, the developer, one of whose partners is zoning attorney John T. (Til) Hazel Jr., has not filed an amendment to its conceptual plan. A spokesman for Hazel/Peterson refused comments on the company's offer to sell land to Mohasco.

Fair Lakes is zoned for a planned development community with 5.1 million square feet of offices, 4.07 million square feet of commercial use and 1,321 residential units. TRW will build 1.4 million square feet of offices. Other clients that have leased space are Group Health Insurance and the Armed Forces Communications and Electronics Association.

Already, Mohasco's subsidiary, Cort Furniture Rental, has a headquarters on Williams Drive in Fairfax County and five outlets in the metropolitan area. The company would consolidate the Cort Rental headquarters at the Fair Lakes site.

The marketing director for the county Economic Development Authority, Alan Gasser, said Mohasco has no plans to move manufacturing operations here, just its administrative offices. The corporation has scouted Montgomery County and other parts of the country for locations, so news that it might settle in Fairfax County is something of a coup, Gasser said.

Mohasco is ranked 372 in the Fortune 500 listings this year, up from 424 three years ago. It is a growing corporation, with net sales in 1984 of $643.8 million, 11 percent higher than the previous year. Its brand names include Mohawk, Alexander Smith and Firth carpets and Futonian's upholstered furniture.