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适用范围：<p>The boiling ferric sulfate-sulfuric acid test may be applied to the following alloys in the wrought condition:<p id="n00001"><table summary="TABLE 1" frame="void" id="n00001" class="rules"> <tr><td align="center" valign="top">Alloy</td><td align="center" valign="top"> Testing Time, h</td></tr> <tr><td align="center" valign="top"></td><TD> </TD></tr> <tr><td align="center" valign="top">N06007</td><td align="center" valign="top"> 120</td></tr> <tr><td align="center" valign="top">N06022</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N06030</td><td align="center" valign="top">120</td></tr> <tr><td align="center" valign="top">N06059</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N06200</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N06455</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N06600</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N06625</td><td align="center" valign="top">120</td></tr> <tr><td align="center" valign="top">N06686</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N06985</td><td align="center" valign="top">120</td></tr> <tr><td align="center" valign="top">N08020</td><td align="center" valign="top">120</td></tr> <tr><td align="center" valign="top">N08367</td><td align="center" valign="top"> 24</td></tr> <tr><td align="center" valign="top">N08800</td><td align="center" valign="top">120</td></tr> <tr><td align="center" valign="top"> N08825^{<span class="italic">A</span>}</td><td align="center" valign="top">120</td></tr> <tr><td align="center" valign="top">N10276</td><td align="center" valign="top"> 24</td></tr> <tr><td align="left" valign="top">____________</td><TD> </TD></tr></table><p class="tablenotes"> ^{<span class="italic">A</span>} While the ferric sulfate-sulfuric acid test does detect susceptibility to inter- granular corrosion in Alloy N08825, the boiling 65 % nitric acid test, Practices A 262<astmref rid="a00001">, Practice C, for detecting susceptibility to intergranular corrosion in stainless steels is more sensitive and should be used if the intended service is nitric acid.</p> </p></p> <p>This test method may be used to evaluate as-received material and to evaluate the effects of subsequent heat treatments. In the case of nickel-rich, chromium-bearing alloys, the test method may be applied to wrought and weldments of products. The test method is not applicable to cast products.</p><p id="s00002">1.1 These test methods cover two tests as follows:</p> <p id="s00003">1.1.1 <span class="italic"><span class="italic">Method A, Ferric Sulfate-Sulfuric Acid Test </span><span class="med">(Sections 3-10, inclusive)</span>8212;</span>This test method describes the procedure for conducting the boiling ferric sulfate<span class=''unicode''>x2014;</span>50 % sulfuric acid test which measures the susceptibility of certain nickel-rich, chromium-bearing alloys to intergranular corrosion (see Terminology G 15<astmref rid="a00003">), which may be encountered in certain service environments. The uniform corrosion rate obtained by this test method, which is a function of minor variations in alloy composition, may easily mask the intergranular corrosion components of the overall corrosion rate on alloys N10276, N06022, N06059, and N06455.</p> <p id="s00004">1.1.2 <span class="italic"><span class="italic">Method B, Mixed Acid-Oxidizing Salt Test </span><span class="med">(Sections 11-18, inclusive)</span>8212;</span>This test method describes the procedure for conducting a boiling 23 % sulfuric + 1.2 % hydrochloric + 1 % ferric chloride + 1 % cupric chloride test which measures the susceptibility of certain nickel-rich, chromium-bearing alloys to display a step function increase in corrosion rate when there are high levels of grain boundary precipitation.</p......