Bankers and money market experts forecast yesterday that the Federal Reserve Board's decision to boost interest rates and adopt strict controls over credit will result immediately in a strengthened dollar and ultimately in reduced inflation in the economy.

At the same time, they warned of very unsettled money and gold trading starting today and concluded that American consumers and business executives will have a much more difficult time finding money to borrow.

American Bankers Association President John H. Perkins, who also is president of Continental Illinois National Bank in Chicago, hailed the Federal Reserve actions on Saturday as "tough medicine" that will hurt some borrowers and some members of his industry, in particular large banks active in overseas lending.

Other bankers said lending officers would be extremely cautious, starting for new loans or extensions of credit.

Speaking to reporters in New Orleans, where the bankers opened their national convention Friday, Perkins agreed with Federal Reserve officials in stating that no credit crunch -- a situation where all bank lending would come to a halt -- should develop.

Rather, Perkins forecast a substantial slowdown in the rate of credit growth without any further sharp interest rate increases -- except during a transition period over the next several weeks.

Only by eliminating the expectations of Americans that inflation will continue unabated in its record upward spiral of recent months "can we get ahold of inflation itself," Perkins declared.

"This is tough medicine that this country needs and needs very badly . . . we must break the back of inflationary fever and I hope this will do the job," he added.

There was some speculation yesterday that Federal Reserve Board Chairman Paul Volcker returned to Washington last week from international banking meetings in Belgrade with something of an ultimatum to the United States to act on inflation.

Sources said Volcker sought White House support for the array of tough new credit controls, in advance, and press secretary Jody Powell endorsed the central bank's action as soon as it was announced late Saturday.

One banker said Volcker had confided privately that earlier measures clearly were not working and that the Federal Reserve would have to assume the leadership in bringing about change. Reportedly, if the decisions announced Saturday do not have the desired quick impact, Volcker has additional proposals under study to tighten credit by successive notches.

The decisions of Saturday, increasing to 12 percent from 11 percent the interest rate for bank borrowings from the central bank and adding new requirements for setting aside reserve money on some key bank lending activities, indicate the United States is finding that foreign developments are having a strong impact on the domestic economy.

But an unanswered question is whether Congress and the White House will be willing to accept the consequences of stringent monetary policy in an election year, for it could trigger recession and a very slow recovery thereafter.

A District of Columbia banker, National Savings & Trust Co. vice chairman Leo M. Bernstein, welcomed the Federal Reserve actions, which most bankers judged to be more stringent than the Carter administration's package of measures a year ago to shore up the dollar.

But he said, "I don't believe National Savings will move our rates very much, if at all, since they are probably as high as they should go . . . this is an effective program, prices will level off."

Perkins said the federal funds rate -- that charged by one bank for overnight lending to another -- may change hourly over the next several months because the Fed has abandoned a policy of trying to control money and credit growth by setting targets for this lending.

Gold prices, which have soared to record levels in recent weeks, may fall. "On the whole, it was a positive move," said Drexel Burnham Lambert analyst Andre Sharon in New York. "The effect on gold prices should be negative," taking speculators by surprise and keeping them off balance, he added.

At the same time, Sharon warned that foreigners have been "disappointed far too often" by U.S. actions aimed at halting the inflationary spiral.

"Although it is very positive because it has the full force of the Federal Reserve behind it, unlike last November's rescue operation which was largely a White House operation, the sharp move to contain money growth will probably trigger a long, tough recession," Sharon said, and markets will watch to see if the United States is "prepared to take the pain of deflation," Sharon stated.

Perkins, whose bank is the seventh largest in the United States, said some stability should be restored to markets within a few months, after which the inflationary spiral will have been halted and interest rates would head down.

Perkins also disputed the consensus view of economists that the United States already is in a recession. He said strong business in most economic sectors coupled with the recent decline in unemployment indicate a better economy than has been recognized but one headed into deep recession because of soaring inflation.

By acting now to halt credit growth, the Federal Reserve may have insured that a recession will be milder when it occurs, Perkins said.