經濟部屮央標準局员工消ίϊ·合作杜印¾ 1 五、發明説明（1 ) 本發明偽有關於一種利用相角偵測裂缝之方法，特別 是有關於一種可監測材料表面裂縫的出現及其延伸，且可 以用來決定引發材料裂缝之陰離子之臨界濃度的利用相角 5 偵測裂縫之方法。 按，材料常會有劣化產生裂缝的可能，瞽如因為接近 熱源，而產生敏化現象，若此時再加上侵蝕性的.離子，會 使材料被腐蝕產生裂縫，嚴重劣化，進而影饗材料的正常 使用。為及早發現裂缝，以作因應措施，因此有數 關專 10 利被提出，以解決此一問題。 在歐洲第t〇一二四號專利案中，利用量測被測物局 部的表面電位變化，籍以判斷被測物表面受破壞的程度。 然而，在該案必須外加一參考電極，並將試Η作鈍化處理 ，以控制電位。而參考電極在溶液中，若長時間測試，易 15 生變化、電位會有褊移（shift )現象.使結果產生誤差。同 時，被測物必須化鈍化處理，故，事先需了解被測物的鈍 化持性，否則無法被應用於判斷其破壊程度。是以，應用 並不便利，同時，量测之精度（尤其是參考電極的電位偏 移）有待改善。 20 而在美國第四〇四八五五八號專利案中，利用金屬表 面裂縫周圍產生的阻抗變化，以不斷增加頻率，偵測裂縫 。但在此案中，被測物表面需點焊訊號接收點，以量測阻 抗變化，而訊號的反應，會因被_物所處的環境，如溫度 或液體的流速，會干擾、影盤測試結果，因而判別不易。 (請先閲請背而之注意事項再填寫本頁) 裝· 訂_ 線. 本紙张尺度边用中國S家標毕（CNS) Ή規格（210父297公龙） 81. 6. 10,000張（Η) Λ 6 Η 6 經濟部屮央標準局ΒΪ工消#合作杜印製 五、發明説明（2 ) 而法國第二二七四〇四二號專利案中，使用一具有兩 阻抗的探針，利用阻抗的改變，使電位產生變化，而測得 金鼷缺陷情況，但此探針當被测物載有載有腐蝕性物質時 ，即會受腐蝕而影镨電位的準確性，應用範圍受限不小。 又在美國第四三〇七六一〇號專利案中，利用高頻萑 動器，量測被測物裂缝的延伸。但此法卻僅限於有負載循 環（Load Cycles )下使用，應用範圍亦是不廣。 有鑑於此，本發明之目的，即在於解決上述問題，其 提供一種偵測裂缝的方法，具有更寛廣的應用範圍，並得 更便利、更精確的量出結果者。 同時，本發明的另一目的，在於提供一種偵測溶液臨 界濃度的方法，得較傳統官試錯誤（trial error )的偵測法， 更為簡便，更為精確者。 為達到上述目的，本發明利用交流阻抗的原理，假定 被測物表面是由電阻（R)和電容（C),以串聯或並聯的方式結 合，不一樣的頻率測式下會出現相角的變化。同樣的情形 ，只要被測物表面之假定電阻或電容發生變化，固定頻率 量測之相角也會有明顯的變化。請參第1A圖，其為一簡單 的線路圖。其中ΚΩ為溶液電阻；R為試K表面電阻；C為 電容。從電路學上的觀點，第1Α圖的電路可以表示如下： Z = Z、jZ"=RQ + R/( KiwRC )……(1) o>=2/if , f為頻率；相角Θ ,可以表示如下： (請先閲讀背而之注意事項再填彭本页j 裝· 訂 線. 本紙a尺度边用中a B家楳準(CNS)甲4規格(210X297公;II·) 81. 6. H),〇〇〇張（H) Λ 6 Β 6 經濟部屮央標準局β工消伢合作杜印製 i 五、發明説明（3 ) tan Θ =1 / ( ω R C)......(2) 根據方程式（2)，吾人可以計算R或C變化時，對相角的影 眢程度。 5 第1B圖為R當成變數時，相角並不會有隨時間增加的 趨勢；但是當C當成變數時，由第1C圖可以知道某些待定 頻率，可以反應出相角隨時間增加的傾向。也就是説當被 測物表面有裂缝產生時，電容（C)值卽發生變化，隨著裂缝 的延伸，此電容值不斷的增大，固定頻率量測之相角，也 10 跟著變化，因此本發明之偵測技術即是利用此持徵，先選 定可使被測物產生裂縫之溶液，使被測物得以產生裂縫。 其次，選定可使被測物之相角隨箸測試時間上升的一定頻 率（因為，並非所有的頻率，都會讓被測物產生裂缝時， 其相角會隨測試時間上升。），再將被測物與前述之溶液 15 接觸，並設置輔助電極，使被測物得以與輔助電極形成迴 路。而後，對被測物施予前述選定頻率的交流電，再經由 檢測被測物之相角變化，而判斷被測物有無裂缝產生，達 到發明目的。 以下，就圖式説明本發明之利用相角偵测裂缝之方法 20 的實施例。 圖式簡單説明： 第1A圖為本發明應用原理之一簡單線路圖。 第1B圖為第1A圈中，被測物無裂缝時，相角與r的關 体圖。 -5 - (請先閲請背而之注意事項寫本頁) 本紙張尺度逍用中國國家樣準(CNS)規格(210x297公幻 81. 6. ]〇,0〇〇張（Η)Employee Consultation and Cooperation of the Bureau of Standards and Biology of the Ministry of Economic Affairs · Du Dui ¾ 1 5. Description of the Invention (1) The present invention relates to a method for detecting cracks using phase angle, in particular, it relates to a method for monitoring the appearance of cracks on the surface of materials and It extends, and can be used to determine the critical concentration of the anion that initiates the cracking of the material. The phase angle 5 is used to detect cracking. Pressing, the material often has the possibility of deterioration and cracks. For example, because it is close to the heat source, it will cause sensitization. If aggressive ions are added at this time, the material will be corroded and cracks will occur, which will seriously deteriorate and then affect the material. Normal use. In order to find cracks as early as countermeasures, several patents have been proposed to solve this problem. In the European Patent No. t012, the surface potential of the measured object is measured to determine the degree of damage to the surface of the measured object. However, in this case, a reference electrode must be added, and the test should be passivated to control the potential. However, if the reference electrode is in the solution, if it is tested for a long time, it will easily change and the potential will shift. This will cause errors in the results. At the same time, the test object must be passivated, so it is necessary to understand the passivity of the test object in advance, otherwise it cannot be used to judge the degree of damage. Therefore, the application is not convenient, and at the same time, the accuracy of measurement (especially the potential deviation of the reference electrode) needs to be improved. 20 In the US Patent No. 404585, the impedance changes around the cracks on the metal surface are used to continuously increase the frequency to detect cracks. However, in this case, the signal receiving point needs to be spot welded on the surface of the measured object to measure the impedance change, and the signal response will be disturbed and shadowed by the environment in which the object is located, such as temperature or the flow rate of the liquid. The test results are not easy to judge. (Please read the precautions before filling in this page) Binding · Binding _ Line. The size of this paper uses the Chinese S home standard (CNS) Ή specification (210 father 297 male dragon) 81. 6. 10,000 sheets ( Η) Λ 6 Η 6 The Ministry of Economic Affairs, Bureau of Standards, ΒΪ 工 消 # Cooperation, Du Printed 5. Description of the invention (2) In the French Patent No. 2274402, a probe with two impedances was used , The change of impedance is used to change the potential, and the defect of the gold alloy is measured, but this probe will be corroded and affect the accuracy of the praseodymium potential when the measured object contains corrosive substances. Restricted is not small. In the US Patent No. 307,610, a high-frequency actuator was used to measure the crack extension of the test object. However, this method is limited to use under load cycles (Load Cycles), and the application range is not wide. In view of this, the purpose of the present invention is to solve the above-mentioned problems. It provides a method for detecting cracks, which has a wider application range, and can more conveniently and accurately measure the results. At the same time, another object of the present invention is to provide a method for detecting the critical concentration of a solution, which is simpler and more accurate than the traditional method for detecting trial error. In order to achieve the above purpose, the present invention uses the principle of AC impedance, assuming that the surface of the measured object is composed of resistance (R) and capacitance (C), connected in series or parallel, and the phase angle will appear under different frequency measurement types. Variety. In the same situation, as long as the assumed resistance or capacitance on the surface of the measured object changes, the phase angle of the fixed frequency measurement will also change significantly. Please refer to Figure 1A, which is a simple circuit diagram. Where KΩ is the solution resistance; R is the K surface resistance; C is the capacitance. From a circuit point of view, the circuit in Figure 1Α can be expressed as follows: Z = Z, jZ " = RQ + R / (KiwRC) ... (1) o > = 2 / if, f is frequency; phase angle Θ, It can be expressed as follows: (Please read the precautions before filling in this page. J Binding and Threading. This paper is used in a standard side a B Family Standard (CNS) A 4 specifications (210X297; II ·) 81. 6. H), 〇〇〇 Zhang (H) Λ 6 Β 6 The Ministry of Economic Affairs, the Central Bureau of Standards, β-consumer cooperation, du printing i. 5. Description of the invention (3) tan Θ = 1 / (ω RC) ... ... (2) According to equation (2), one can calculate the degree of influence on the phase angle when R or C changes. 5 Figure 1B shows that when R is a variable, the phase angle does not tend to increase with time; but when C is a variable, some frequencies to be determined can be known from Figure 1C, which can reflect the tendency of the phase angle to increase with time. . In other words, when a crack occurs on the surface of the measured object, the capacitance (C) value changes. As the crack extends, the capacitance value continues to increase, and the phase angle measured at a fixed frequency also changes with 10, so The detection technology of the present invention utilizes this feature to first select a solution that can cause the test object to crack, so that the test object can crack. Secondly, select a certain frequency that can increase the phase angle of the measured object with the test time (because not all frequencies will cause the measured object to crack, the phase angle will increase with the test time.), And then will be The test object is in contact with the aforementioned solution 15, and an auxiliary electrode is provided so that the test object can form a loop with the auxiliary electrode. Then, the alternating current of the selected frequency is applied to the test object, and then the phase angle change of the test object is detected to determine whether the test object has cracks, which achieves the purpose of the invention. Hereinafter, an embodiment of the method 20 for detecting cracks using phase angles of the present invention will be described with reference to the drawings. Brief description of the drawings: Figure 1A is a simple circuit diagram of one of the application principles of the present invention. Figure 1B shows the relationship between the phase angle and r when the measured object has no cracks in circle 1A. -5-(Please read the notes on the back to write this page) This paper standard uses the Chinese National Standards (CNS) specifications (210x297 公 幻 81. 6.) 〇, 0〇〇 Zhang (Η)
} 五、發明说明（4 ) 第1C圖為第1A圖中，被測物有裂缝時，相角與R的鞠 係圖。 第2圖為本發明一較佳具體實施例之測試糸統圖。 5 第3圖為上逑實施例之測試系統使用步驟圖； 第4圖偽顯示對不同狀態的不鏽鋼所作之偵測的相角 變化圖表。 第5圖係顯示偵測完畢後有缺陷不鏽鋼的放大圔； 第6圖偽顯示以不同頻率對不鏽鋼所作之偵測的相角 10 變化圖表； 第7圖偽顯示以不同的溶液濃度對不鏽辆所作之偵锏 的相角變化圖表； 第8圖偽顯示以10 Hz的頻率對銅一鋅合金所作之偵测 的相角變化圖表； 15 第9圖係顯示在第8圖中之（A)、⑻及（C)三階段之材料 的放大圖； 第10圖偽顯示以10Hz之頻率在Ka2S〇4中對銅一鋅合金所 作之偵测的相角變化圖表； 經濟部屮央標準局员工消tv合作社印製 -r>靖先間請背而之逄意事項畀填窍未頁) %. 第11圖偽顯示以10Hz之頻率在缓衝溶液中對銅一鋅合 20 金所作之偵測的相角變化圖表； 第12圖係顯示偵測完畢後有缺陷銅一鋅合金的放大圖 9 第13圖偽顯示以不同頻率對銅一鋅合金所作之偵測的 相角變化圖表。 本紙張尺度边用中a Η家棋準(CNS)甲4規格(210X297公；«:) 81. 6.】〇,〇〇〇張（Η) A 6 Π 6 1 五、發明説明（5 ) 諳參照第2圖及第3圖，第2圖偽顯示本發明一較佳 實施例的測試条統圖；第3圖為第2圖實施例条統的偵测 方法步驟圖。本發明之利用相角偵測裂缝之·方法適用於藉 5 由訊號分析處理糸統（訊號分析儀及含有電腦軟體的電腦 處理糸統）來分析不同材質之被測物10的相角變化。本發 明之方法包括下列步驟：選定具侵蝕性離子溶液20 (例如 ，含氣離子溶液、含硫氛溶液等等的測試溶液）；準備頻 率產生器，選定一定的頻率，而該頻率得使被測物之相角 10 隨測試時間上升，用以輸出各種頻率的交流電；將被測物 10連接至頻率產生器，並將被測物10浸置於測試溶液20中 並設置輔助電極30 ,使被測物10與輔肋電極30形成迴路； 再使頻率產生器產生既定頻率的交流電；並藉由訊號分析 處 15 理系統來分析被測物10的相角變化，以判定被測物10是否 有裂缝產生，並得在預測物有裂縫時，發出螯告。此外， 測試溶液20的濃度可被漸漸地增加，重覆判斷被測物有無 裂縫產生，以判定造成裂缝之陰離子濃度的臨界濃度之值 Ο 經濟部屮央標準局员工消伢合作社印^ (請先閲讀背而之注意事項洱蜞寫本頁) 20 所使用的輔助電極30 ,可選用的鈍性金颶，如：白金 ，因其穩定，不參與反應（因其並非如前述歐洲第t〇一 二四號專利案中，作為參考電極使用）、不易受環境影蜜 ，故可使量測更為正確、更費用。 實施例一 -7 - 本紙張尺度边用中國S家樣準(CNS)T4規格(210x297公*) 81. 6, 10,000張（H) 經濟部屮央標準局β工消设合作杜印則4 21¾¾80 1 五、發明説明（6 ) ⑴測試條件 被測物：敏化304不鏽鋼和未敏化304不鏽鋼 測試溶液：0.5M Na2S2〇3 5 溫度：50 1C 頻率：20 Hz ⑵裂缝偵測 如第4圖” A”線所示，當浸置時間超過60秒時，U型 敏化304不鏽銷試Η的相角（Phase Angle)即開始攀升，随箸裂 10 缝的延伸，相角不斷的增加。倘被测物為未敏化304不鏽 鋼（第4圖” B”線），隨箸浸置時間的加長，相角並设有 攀升的趨勢，反而是往下降，而且趨於一穩定值。测試完 畢，檢視被測試Η外觀，未敏化304不鏽鏑試Η完好如初， 而敏化304不鏽鋼則出現如第5Α圖之裂缝，其破斷面為典型 15 之沿晶應力腐独（Intergranular stress Corrosion Cracking ， IGSCC)型 態，如第5B圖所示。 (3)腐蝕過程之影繼： 為了探討被測物腐蝕時是否同樣會造成相角的攀升現 象，將斷裂成兩半之U型試Η的另一半浸置於測試溶液中 20 ，以20Hz的頻率，量測試Κ的相角變化，結果如第4圖Τ” 線所示。基本上，相角維持在一定範圍内，並沒有明顯的 攀升趨勢，也就是相角之增加主要是裂缝延伸所造成，腐 蝕過程並不會明顯干擾相角的變化。 將敏化304不鏽鋼試Η，在不受力之情況下，也就是不 -8 - Λ 6 Η 6 (請先閲讀背而之注意事項再塡寫本頁) 本紙張尺度逍用中國8家樣準(CNS)T4規格(210x297公;¢) 81. 6. 10,000張（H) Λ 6 Η 6 經濟部屮央棵準局貞工消仲合作社印奴 1 五、發明説明（7 ) 彎曲成U型試κ之狀態下浸置於測試溶液，以20Hz的頻率 量測其相角變化，結果如第4圖"D”線所示。偵測過程中， 雖有腐蝕發生，但是相角呈下降之趨勢，最後趨於一穩定 5 值，再一次驗証相角的攀升是由於裂缝延伸所造成。腐蝕 過程不會干擾相角的變化。 ⑷適用頻率 將U型敏化304不鏽鋼試K浸置於測試溶液中，利用不 同的頻率（20KHz〜2Hz)觀察試Η之相角變化，基本上，被測 10 物經過3600秒的測試以後，U型試Κ皆呈IGSCC破斷，但是丰目 角則有不同的變化。由第6圈可知當頻率2 2ΚΗζ時，相角 在初期雖有增加，在後期卻有下降的趨勢；當頻率S 2Hz時 ,相角則呈下降，而後趨於一穩定值。此種現象乃是基於 交流阻抗（AC Impedance)之特性：頻率太高，旨在探討測試溶 15 液之性質；頻率太低，無法完全反應出被測物表面之持性 ，惟有在適當的頻率範圔，才能真正反應出表面裂缝及其 延伸特性。 ⑸臨界濃度決定 本發明，除了可以監測裂缝的出現和延伸外，亦可用 20 來決定會產生裂缝之臨界陰離子濃度之量。將U型敏化304 不鏽網試Η浸置於50°C之Na2S2〇3中，施以200Hz頻率之交流電 ，其相角變化如第7圖所示（圖中，此&〇3的濃度；A為 0ppm ; B 為 100ppb ; C 為lppm ; D 為 10ρρΐΒ ; E 為 100ppm );當 Na&O3濃度S 10ppm時，相角維持在一穩定值；但是當 (請先閲讀背而之注意事項#填寫本頁) 本紙尺度遴用中a B家標準（CNS) T4規格（2丨0X297公龙) 81. 6. 10,000¾ (H) 經濟部屮央標準局Α工消仲合作杜印3i aiaaaa V .. )、 . Γ . 1 五、發明説明（8) Na2S2〇3濃度δ 100ppm時由於測試溶液導電度之變化，導致相 角於初期有下降趨勢，但是經過一段時間後，相角即有攀 升之現象，此結果意諝箸U型敏化304不鏽鋼在100ppm Na2S2〇3 5 濃度中，即會有裂缝產生。 實施例二 ⑴測試條件： 被测物：銅-鋅合金（70/30黃銅） 測試溶液：NH40H 10 溫度：室溫 ⑵裂縫偵測 將測試頻率固定於10Hz，結果如第8圖所示。當浸置時 間超過100秒，銅-鋅合金試Η的相角即開始往上攀升，隨 箸裂缝的延伸，相角不斷的增加；當裂縫貫穿試Η時，相 15 角之值會趨於一穩定值。第8圖中（Α),⑻和（C)三階段的試 Η外觀，如第9圖所示，值得注意的是：⑷階段需放大 2540倍才可看清裂缝之出現，⑻階段需放大803倍，而（C)階 段衹需296倍，即可很清晰的看清裂缝外觀。此結果説明若 試Η上有裂缝出現，相角即可反應偵測出裂缝的出現；隨 20 裂缝的延伸，相角即不斷的增加，由（A)，（Β)和（C)三階段的 相角變化，即可發現此趨勢。 ⑶腐蝕過程之影鎏 將銅-鈴合金試Κ ,浸置於和緩衝溶液中，以10Hz 之頻率測試相角之變化，結果分別由第10圖和第11圖所示 -10 - Λ 6 Ιϊ 6 (請先閲讀背而之注意事項4塡窍本頁) 裝· 訂· 線· 本紙張尺度逍用中a a家楳準(CNS) T4規格(210X297公龙) 81. 6. 10,000張（H) 經濟部屮央榀準局员工消#合作社印5i 1 五、發明説明（9 ) 。基本上，在上述溶液中，相角隨時間呈現遞減的現象， 雖然腐蝕現象會造成相角的異動，然而未如第8圈之相角 增加之趨勢。換言之，銅-鋅試Κ於上述兩種溶液中，並 5 不會有裂縫延伸，因此相角無法偵測出。試Η測試完後， 以高倍（> 册0倍）顯徹鏡觀查外觀，並無裂缝出現。 ⑷適用頻率 將U型銅-鋅合金試Μ浸置於含銅粉之ΝΗ40Η溶液中， 利用不同頻率（10ΚΗΖ〜0.1Ηζ)測試相角變化。基本上，被測物 10 測試完畢後，裂缝破斷面呈沿晶和穿晶之混合破裂外觀（ 第12圖）；但是相角則有不同的變化，由第13圖可知，當 頻率，f ,為10Hz S f S 100Hz時，相角可以很成功的偵测 出裂缝的延伸。 如上所述，依據前述發明之利用相角偵測裂缝之方法 15 ，由於S由將被測物浸置於具侵蝕性離子溶液中，並施加 一既定頻率之交流電，故可應用於各種材質及形狀的材料 ，且不受環境因素影镨。 同時，在應用層面上，當被测物為一儲槽、或者是一 流動的管路（内有溶液），只要適當的設置輔助電極，皆 20 可應用本發明來量測，是以，本發明應用範圍相當廣。 雖然本發明以一較佳實施例掲露如上，然其並非用以 限定本發明，任何熟悉此項技藝者，在不脱離本發明之精 神和範圍内，當可作些許之更動與潤飾，因此本發明之保 護範圍當視申請專利範圍所界定者為準。 -11 - Λ 6 Π 6 (請先閱讀背而之注意事項再璜寫本頁) 裝- 訂_ 線< 本紙张尺度边用中a Η家搮毕（CNS)肀4規格（210x297公;«：) 81. 6.丨0,000張（Η)} 5. Description of the invention (4) Figure 1C is the diagram of the phase angle and R when the measured object has cracks in Figure 1A. Figure 2 is a test diagram of a preferred embodiment of the present invention. 5 Figure 3 is a diagram of the steps of using the test system of the previous embodiment; Figure 4 is a pseudo-display of the phase angle change chart for the detection of stainless steel in different states. Figure 5 shows the enlarged scale of the defective stainless steel after the detection; Figure 6 pseudo shows the phase angle 10 change chart of the detection of stainless steel at different frequencies; Figure 7 pseudo shows the different solution concentrations against stainless Diagram of the phase angle change of the vehicle's detection; Figure 8 pseudo-displays the phase angle change chart of the detection of the copper-zinc alloy at a frequency of 10 Hz; 15 Figure 9 is shown in Figure 8 (A ), ⑻ and (C) the enlarged view of the three-stage material; Figure 10 pseudo-displays the phase angle change chart of the detection of copper-zinc alloy in Ka2S〇4 at a frequency of 10 Hz; Printed by the Employee Consumer TV Co-op-r > Jing Xian, please turn your backs into consideration and fill in the tips.%. Figure 11 shows a pseudo display of copper-zinc alloy 20 in buffer solution at a frequency of 10 Hz The detected phase angle change chart; Figure 12 is an enlarged view of the defective copper-zinc alloy after the detection is completed. Figure 13 pseudo-displays the phase angle change chart of the copper-zinc alloy detected at different frequencies. The size of the paper is used in the middle of a Η 家 棋 准 (CNS) A 4 specifications (210X297 public; «:) 81. 6.] 〇, 〇〇〇 Zhang (Η) A 6 Π 6 1 V. Invention description (5) Refer to Fig. 2 and Fig. 3, Fig. 2 pseudo-displays a test profile of a preferred embodiment of the present invention; Fig. 3 is a step diagram of the method of detecting the profile of the embodiment of Fig. 2. The method for detecting cracks using phase angle of the present invention is suitable for analyzing the phase angle change of the test object 10 of different materials by the signal analysis processing system (signal analyzer and computer processing system containing computer software). The method of the present invention includes the following steps: selecting an aggressive ionic solution 20 (for example, a test solution containing a gas-containing ion solution, a sulfur-containing atmosphere solution, etc.); preparing a frequency generator, selecting a certain frequency, and the frequency must be The phase angle 10 of the test object rises with the test time and is used to output alternating current of various frequencies; connect the test object 10 to the frequency generator, and immerse the test object 10 in the test solution 20 and set the auxiliary electrode 30 so that The measured object 10 and the auxiliary rib electrode 30 form a loop; then the frequency generator generates alternating current of a predetermined frequency; and the signal analysis processing system 15 analyzes the phase angle change of the measured object 10 to determine whether the measured object 10 Cracks occur, and you must issue a cheat when the predicted object has cracks. In addition, the concentration of the test solution 20 can be gradually increased. Repeat to determine whether the test object has cracks, to determine the critical concentration value of the anion concentration that caused the crack. The employee of the Ministry of Economic Affairs Bureau of Standards and Industry Cooperative Print ^ (please Read the back-to-back precautions first and write this page) 20 The auxiliary electrode 30 used, the optional passive gold hurricane, such as: platinum, because of its stability, does not participate in the reaction (because it is not the same as the aforementioned European t. It is used as a reference electrode in the patent case No. 12 or 4), which is not easy to be affected by the environment, so it can make the measurement more accurate and more costly. Example 1-7-This paper uses the Chinese S Home Sample Standard (CNS) T4 specifications (210x297 g *) 81. 6, 10,000 sheets (H) The Ministry of Economic Affairs, Bureau of Standards, Beta-Consumer Cooperation, Du Yinze 4 21¾¾80 1 V. Description of the invention (6) (1) Test conditions Test object: sensitized 304 stainless steel and unsensitized 304 stainless steel Test solution: 0.5M Na2S2〇3 5 Temperature: 50 1C Frequency: 20 Hz ⑵ Crack detection as the 4th As shown in the "A" line of the figure, when the immersion time exceeds 60 seconds, the phase angle of the U-sensitized 304 stainless pin test H begins to climb, and the phase angle continues to increase with the extension of the 10 cracks. increase. If the test object is unsensitized 304 stainless steel (line 4 “B” in Figure 4), as the immersion time of the chopstick increases, the phase angle has a rising trend, but instead it goes down and tends to a stable value. After the test, check the appearance of the tested H. The unsensitized 304 stainless dysprosium test H is intact as before, while the sensitized 304 stainless steel has cracks as shown in Figure 5A, and its fracture surface is typical of 15 intergranular stress corrosion ( Intergranular stress Corrosion Cracking (IGSCC), as shown in Figure 5B. (3) The shadow of the corrosion process continues: In order to explore whether the test object will also cause the phenomenon of climbing the phase angle, the other half of the U-shaped test H that is broken in half is immersed in the test solution 20 at 20 Hz. Frequency and quantity test the phase angle change of K, and the result is shown as the T line in Figure 4. Basically, the phase angle is maintained within a certain range, and there is no obvious climbing trend, that is, the increase of the phase angle is mainly caused by the crack extension As a result, the corrosion process will not significantly interfere with the change of phase angle. The sensitized 304 stainless steel will be tested Η, without stress, that is, not -8-Λ 6 Η 6 (Please read the precautions first (This page is written on this page.) This paper uses the 8 Chinese standards (CNS) T4 specifications (210x297 g; ¢) 81. 6. 10,000 sheets (H) Λ 6 Η 6 The Ministry of Economic Affairs, the Central Bureau of the Ministry of Economic Affairs Cooperative Innu 1 V. Description of the invention (7) Immersed in the test solution in a state of bending into a U-shaped test κ and measuring the change of its phase angle at a frequency of 20 Hz. The results are shown in the "D" line in Figure 4. During the detection process, although corrosion occurred, the phase angle showed a declining trend, and finally tended to a stable value of 5, and once again verified that the rise of the phase angle was caused by crack extension. The corrosion process does not interfere with the change of phase angle. ⑷Applicable frequency The U-sensitized 304 stainless steel test K is immersed in the test solution, and the phase angle of the test H is observed using different frequencies (20KHz ~ 2Hz). Basically, after the test object has passed the test for 3600 seconds, The U-shaped test K showed broken IGSCC, but the Fengmu angle has different changes. From the sixth circle, we can see that when the frequency is 2 2ΚΗζ, the phase angle increases in the early stage, but has a tendency to decrease in the later stage; when the frequency S 2Hz, the phase angle decreases, and then tends to a stable value. This phenomenon is based on the characteristics of AC Impedance: the frequency is too high to explore the nature of the test solution; the frequency is too low to fully reflect the persistence of the surface of the test object, but only at an appropriate frequency Fan Fan can truly reflect the surface cracks and their extension characteristics. ⑸Critical concentration determination In the present invention, in addition to monitoring the occurrence and extension of cracks, 20 can also be used to determine the amount of critical anion concentration that will cause cracks. Immerse the U-shaped sensitized 304 stainless steel mesh in Na2S2〇3 at 50 ° C and apply an alternating current with a frequency of 200 Hz. The phase angle changes as shown in Figure 7 (in the figure, this & 〇3 Concentration; A is 0ppm; B is 100ppb; C is lppm; D is 10ρρΙΒ; E is 100ppm); when the Na & O3 concentration S 10ppm, the phase angle is maintained at a stable value; but when (please read the precautions first Matter # fill out this page) This paper is used in the selection of a B family standard (CNS) T4 specification (2 丨 0X297 male dragon) 81. 6. 10,000¾ (H) Ministry of Economic Affairs, Bureau of Standards, Bureau of Industry, Consumer Affairs and Cooperation Du Yin 3i aiaaaa V ..),. Γ. 1 V. Description of the invention (8) When the concentration of Na2S2〇3 δ is 100 ppm, due to the change in the conductivity of the test solution, the phase angle has a downward trend at the beginning, but after a period of time, the phase angle is There is a climbing phenomenon. This result means that the U-shaped sensitized 304 stainless steel will have cracks in the concentration of 100ppm Na2S203. Example 2 (1) Test conditions: Test object: copper-zinc alloy (70/30 brass) Test solution: NH40H 10 Temperature: room temperature ⑵ Crack detection Fix the test frequency at 10 Hz. The results are shown in Figure 8. When the immersion time exceeds 100 seconds, the phase angle of the copper-zinc alloy test H begins to climb upwards, and the phase angle increases continuously as the cracks extend. When the crack penetrates the test H, the value of the phase 15 angle will tend to A stable value. The appearance of the three phases of (Α), ⑻ and (C) in Figure 8, as shown in Figure 9, it is worth noting that: ⑷ stage needs to be enlarged 2540 times to see the appearance of cracks, ⑻ stage needs to be enlarged 803 times, and (C) stage only 296 times, you can clearly see the appearance of cracks. This result shows that if there is a crack on the test Η, the phase angle can be detected to detect the occurrence of cracks; with the extension of 20 cracks, the phase angle increases continuously, which consists of three stages (A), (B) and (C) Changes in the phase angle can be found in this trend. (3) The shadow of the corrosion process immersed the copper-bell alloy in the buffer solution and tested the change of phase angle at a frequency of 10 Hz. The results are shown in Figure 10 and Figure 11 respectively-10-Λ 6 Ιϊ 6 (Please read the notes on the back of page 4). Binding · Order · Thread · This paper standard for easy use aa Jiayu standard (CNS) T4 specifications (210X297 male dragon) 81. 6. 10,000 sheets (H ) The Ministry of Economic Affairs of the Ministry of Economic Affairs of the Central Bureau of Employee Elimination #Cooperatives printed 5i 1 V. Description of the invention (9). Basically, in the above solution, the phase angle shows a decreasing phenomenon with time. Although the corrosion phenomenon will cause the phase angle to move, it does not increase as the phase angle of the 8th cycle increases. In other words, copper-zinc test K in the above two solutions, and there will be no crack extension, so the phase angle cannot be detected. After the test Η was completed, the appearance of the microscope was examined at a high magnification (> 0 times the volume), and no cracks appeared. ⑷Applicable frequency The U-shaped copper-zinc alloy test immersed in NH40H solution containing copper powder, using different frequencies (10KHZ ~ 0.1Ηζ) to test the phase angle change. Basically, after the test object 10 has been tested, the cracked fracture surface has a mixed fracture appearance of intergranular and transgranular (Figure 12); however, the phase angle changes differently, as can be seen from Figure 13, when the frequency, f , When it is 10Hz S f S 100Hz, the phase angle can successfully detect the crack extension. As described above, according to the method of detecting cracks using phase angle 15 of the foregoing invention, since S is immersed in the analyte in an aggressive ionic solution and applied with a predetermined frequency of alternating current, it can be applied to various materials and The shape of the material is not affected by environmental factors. At the same time, on the application level, when the measured object is a storage tank or a flowing pipeline (with a solution in it), as long as the auxiliary electrode is properly set, the invention can be used for measurement. The scope of application of the invention is quite wide. Although the present invention is disclosed as above in a preferred embodiment, it is not intended to limit the present invention. Anyone who is familiar with this art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be deemed as defined by the scope of the patent application. -11-Λ 6 Π 6 (Please read the precautions before writing this page) Binding-Order _ Line < This paper is used in the standard a Η 家 殮 毕 (CNS) 4 specifications (210x297; «:) 81. 6. 丨 0,000 sheets (Η)