只需将按钮的禁用图标设置为与按钮图标相同的值。请参见此示例：
在左边的一个按钮，我已经设置了图标和禁用图标。在右边，我只设置了图标：

import java.awt.BorderLayout;
import java.net.MalformedURLException;
import java.net.URL;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;

public class TestDisabledButtons {

    public static final String CARD_URL = "http://assets0.wordansassets.com/wvc-1345850020/wordansfiles/images/2012/8/24/156256/156256_340.jpg";

    protected void createAndShowGUI() throws MalformedURLException {
        JFrame frame = new JFrame("Test button");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        ImageIcon imageIcon = new ImageIcon(new URL(CARD_URL));
        JButton button = new JButton(imageIcon);
        JButton button2 = new JButton(imageIcon);
        button.setDisabledIcon(imageIcon);
        button.setEnabled(false);
        button2.setEnabled(false);
        frame.add(button, BorderLayout.WEST);
        frame.add(button2, BorderLayout.EAST);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    new TestDisabledButtons().createAndShowGUI();
                } catch (MalformedURLException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        });
    }

}