ndt定義

是非破壞性試驗的英文（Non-destructive testing）縮寫，是指對材料或工件實施一種不損害或不影響其未來使用性能或用途的檢測手段。通過使用 NDT，能發(fā)現(xiàn)材料或工件內(nèi)部和表面所存在的缺欠，能測量工件的幾何特征和尺寸，能測定材料或工件的內(nèi)部組成、結(jié)構(gòu)、物理性能和狀態(tài)等。

無損檢測技術(shù)是第二次世界大戰(zhàn)后在國際上迅速發(fā)展起來的一門新興的綜合性工程科學(xué)。無損檢測技術(shù)又稱非破壞檢查技術(shù)（N0n-Destructive Testing），顧名思義，就是以不使被檢查物使用性能及形態(tài)受到損傷為前提，通過一定的檢測手段來檢測或測量、顯示和評估物質(zhì)中因有缺陷或組織結(jié)構(gòu)上的差異存在而會使其某些物理性質(zhì)的物理量發(fā)生變化的現(xiàn)象，從而了解和評價材料、產(chǎn)品、設(shè)備構(gòu)件直至生物等的性質(zhì)、狀態(tài)或內(nèi)部結(jié)構(gòu)等等的一種特殊的檢測技術(shù)。在國際上，已經(jīng)得到普遍認(rèn)同：一個國家、一個地區(qū)、一個行業(yè)，直至一個企業(yè)的工業(yè)技術(shù)水平可以通過其無損檢測的技術(shù)水平來反映。

NDT 能應(yīng)用于產(chǎn)品設(shè)計、材料選擇、加工制造、成品檢驗、在役檢查（維修保養(yǎng)）等多方面，在質(zhì)量控制與降低成本之間能起最優(yōu)化作用。NDT還有助于保證產(chǎn)品的安全運行和（或）有效使用。NDT 包含了許多種已可有效應(yīng)用的方法，最常用的 NDT方法是：射線照相檢測、超聲檢測、渦流檢測、磁粉檢測、滲透檢測、目視檢測、泄漏檢測、聲發(fā)射檢測、射線透視檢測等。

由于各種 NDT 方法，都各有其適用范圍和局限性，因此新的 NDT 方法一直在不斷地被開發(fā)和應(yīng)用。通常，只要符合 NDT 的基本定義，任何一種物理的、化學(xué)的或其他可能的技術(shù)手段，都可能被開發(fā)成一種 NDT 方法。

在我國，無損檢測一詞最早被稱之為探傷或無損探傷，其不同的方法也同樣被稱之為探傷，如射線探傷、超聲波探傷、磁粉探傷、滲透探傷等等。這一稱法或?qū)懛◤V為流傳，并一直沿用至今，其使用率并不亞于無損檢測一詞。

在國外，無損檢測一詞相對應(yīng)的英文詞，除了該詞的前半部分——即 Non-destructive 的寫法大多相同外，其后半部分的寫法就各異了。如日本習(xí)慣寫作 inspection，歐洲不少國家過去曾寫作 flaw detection、現(xiàn)在則統(tǒng)一使用 testing，美國除了也使用 testing 外，似乎更喜歡寫作 examination 和 evaluation。這些詞與前半部分結(jié)合后，形成的縮略語則分別是 NDI、NDT 和 NDE，翻譯成中文就出現(xiàn)了無損探傷、無損檢查（非破壞檢查）、無損檢驗、無損檢測、無損評價等不同術(shù)語形式和寫法。實際上，這些不同的英文及其相應(yīng)的中文術(shù)語，它們具有的意義相同，都是同義詞。為此，國際標(biāo)準(zhǔn)化組織無損檢測技術(shù)委員會（ISO/TC 135）制定并發(fā)布了一項新的國際標(biāo)準(zhǔn)（ISO/TS 18173:2005），旨在將這些不同形式和寫法的術(shù)語統(tǒng)一起來，明確它們是有一個相同定義的術(shù)語、都是同義詞，即都等同于無損檢測（Non-destructive testing）。而不同的寫法，僅僅是由于語言習(xí)慣不同而已。

因此，作為標(biāo)準(zhǔn)化的術(shù)語，推薦使用“無損檢測”一詞，對應(yīng)的英文詞則推薦使用“Non-destructive testing”。各種無損檢測方法的名稱，也同樣推薦使用“檢測”一詞，如射線照相檢測、超聲檢測、磁粉檢測、滲透檢測、渦流檢測等等。在翻譯時，與 Non-destructive 相連用的如 inspection、examination、evaluation 等英文詞，都推薦譯成“無損檢測”一詞，盡量避免寫作“無損探傷”、“無損檢查”、“無損檢驗”、“無損評價”等。這一譯法也同樣適用于各種無損檢測方法名稱的譯法。

注：inspection、examination、evaluation 等詞，僅在翻譯無損檢測及其方法的名稱時才推薦譯成“檢測”一詞，其他場合宜依據(jù)原文內(nèi)容和中文習(xí)慣來翻譯。

What's NDT

The field of Nondestructive Testing (NDT) is a very broad, interdisciplinary field that plays a critical role in assuring that structural components and systems perform their function in a reliable and cost effective fashion. NDT technicians and engineers define and implement tests that locate and characterize material conditions and flaws that might otherwise cause planes to crash, reactors to fail, trains to derail, pipelines to burst, and a variety of less visible, but equally troubling events. These tests are performed in a manner that does not affect the future usefulness of the object or material. In other words, NDT allows parts and material to be inspected and measured without damaging them. Because it allows inspection without interfering with a product's final use, NDT provides an excellent balance between quality control and cost-effectiveness. Generally speaking, NDT applies to industrial inspections. Technology that is used in NDT is similar to those used in the medical industry; yet, typically nonliving objects are the subjects of the inspections.

What is NDE"para" label-module="para">

Nondestructive evaluation (NDE) is a term that is often used interchangeably with NDT. However, technically, NDE is used to describe measurements that are more quantitative in nature. For example, an NDE method would not only locate a defect, but it would also be used to measure something about that defect such as its size, shape, and orientation. NDE may be used to determine material properties, such as fracture toughness, formability, and other physical characteristics.

Some NDT/NDE Technologies:

Many people are already familiar with some of the technologies that are used in NDT and NDE from their uses in the medical industry. Most people have also had an X-ray taken and many mothers have had ultrasound used by doctors to give their baby a checkup while still in the womb. X-rays and ultrasound are only a few of the technologies used in the field of NDT/NDE. The number of inspection methods seems to grow daily, but a quick summary of the most commonly used methods is provided below.

Visual and Optical Testing (VT)

The most basic NDT method is visual examination. Visual examiners follow procedures that range from simply looking at a part to see if surface imperfections are visible, to using computer controlled camera systems to automatically recognize and measure features of a component.

Radiography (RT)

RT involves the use of penetrating gamma- or X-radiation to examine material's and product's defects and internal features. An X-ray machine or radioactive isotope is used as a source of radiation. Radiation is directed through a part and onto film or other media. The resulting shadowgraph shows the internal features and soundness of the part. Material thickness and density changes are indicated as lighter or darker areas on the film. The darker areas in the radiograph below represent internal voids in the component.

Magnetic Particle Testing (MT)

This NDT method is accomplished by inducing a magnetic field in a ferromagnetic material and then dusting the surface with iron particles (either dry or suspended in liquid). Surface and near-surface flaws produce magnetic poles or distort the magnetic field in such a way that the iron particles are attracted and concentrated. This produces a visible indication of defect on the surface of the material. The images below demonstrate a component before and after inspection using dry magnetic particles.

Ultrasonic Testing (UT)

In ultrasonic testing, high-frequency sound waves are transmitted into a material to detect imperfections or to locate changes in material properties. The most commonly used ultrasonic testing technique is pulse echo, whereby sound is introduced into a test object and reflections (echoes) from internal imperfections or the part's geometrical surfaces are returned to a receiver . Below is an example of shear wave weld inspection. Notice the indication extending to the upper limits of the screen. This indication is produced by sound reflected from a defect within the weld.

Penetrant Testing (PT)

The test object is coated with a solution that contains a visible or fluorescent dye. Excess solution is then removed from the surface of the object but leaving it in surface breaking defects. A developer is then applied to draw the penetrant out of the defects. With fluorescent dyes, ultraviolet light is used to make the bleedout fluoresce brightly, thus allowing imperfections to be readily seen . With visible dyes, vivid color contrasts between the penetrant and developer make "bleedout" easy to see. The red indications below represent a number of defects in this component.

Electromagnetic Testing (ET)

Electrical currents (eddy currents) are generated in a conductive material by a changing magnetic field. The strength of these eddy currents can be measured. Material defects cause interruptions in the flow of the eddy currents which alert the inspector to the presence of a defect. Eddy currents are also affected by the electrical conductivity and magnetic permeability of a material, which makes it possible to sort some materials based on these properties. The technician below is inspecting an aircraft wing for defects.

Leak Testing (LT)

Several techniques are used to detect and locate leaks in pressure containment parts, pressure vessels, and structures. Leaks can be detected by using electronic listening devices, pressure gauge measurements, liquid and gas penetrant techniques, and/or a simple soap-bubble test.

Acoustic Emission Testing (AE)

When a solid material is stressed, imperfections within the material emit short bursts of acoustic energy called "emissions." As in ultrasonic testing, acoustic emissions can be detected by special receivers. Emission sources can be evaluated through the study of their intensity and arrival time to collect information about the sources of the energy, such as their location.

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按物理原理或檢測對象和目的的不同，無損檢測大致分為如下幾種方法：

a) 滲透檢測（penetrant testing，PT）；

b) 磁粉檢測（magnetic testing，MT）；

c) 目視檢測（visual testing，VT）；

d) 超聲檢測（ultrasonic testing，UT）；

e) 渦流檢測（eddy current testing，ET）；

f) 射線照相檢測（radiographic testing，RT）；

g) 泄漏檢測（leak testing，LT）；

h) 紅外成像檢測（infrared thermographic testing，TT或IT）；

i) 聲發(fā)射檢測（acoustic emission testing，AT或AE） 。2100433B

無損檢測(NDT，Non-destructive testing)等。

AGFA 工業(yè)膠片 AGFA NDT D4 Film (D4 s.c. Film - D4單面涂層膠片)

AGFA NDT D5 Film

AGFA NDT D7 Film（國內(nèi)分切片C7）

KODAK 工業(yè)膠片 主要有AA400產(chǎn)品 及國內(nèi)分切片（了凱LA400型工業(yè)膠片）

其他數(shù)字化產(chǎn)品

富士工業(yè)膠片 原裝自主品牌工業(yè)膠片及國內(nèi)分切片（巨星貿(mào)易（上海）有限公司YESSTAR牌工業(yè)膠片）

德國NDTQUAM 工業(yè)膠片 M7系列