Plastics — Methods of exposure to laboratory light sources -
Part 2:
Xenon—arc lamps
塑料—-—实验室光照老化测试 第二部分——-氙弧灯
1 Scope
This part of ISO 4892 specifies methods for exposing specimens to xenon-arc light in the prence of moisture to reproduce the weathering effects （temperature, humidity and/or wetting) that occur when materials are expod in actual end—u environments to daylight or to daylight filtered through window glass.
此ISO 4892标准中介绍了将试样暴露在氙灯及雨淋环境中，通过模仿自然光或有窗户玻璃过滤状态下的自然环境，以确定终端客户在使用材料时受到自然气候的影响（温度，湿度/或受潮)。
Specimen preparation and evaluation of the results are covered in other International Standards foractualize specific materials。
特殊材料试样的制备以及结果评价参考其他国际标准。
General guidance is given in ISO 4892—1。
通则见ISO 4892—1sonofbitch
NOTE Xenon—arc exposures of paints and varnishes are described in ISO 11341。
注：涂料及清漆的氙灯老化见ISO 11341
2 Normative references
The following documents， in whole or in part, are normatively referenced in this document and are indispensable for its application。 For dated references， only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4582, Plastics - Determination of changes in colour and variations in properties after exposure to daylight under glass, natural weathering or laboratory light sources
ISO 4892—1, Plastics — Methods of exposure to laboratory light sources — Part 1： General guidance
ISO 9370， Plastics — Instrumental determination of radiant exposure in weathering tests — General
guidance and basic test method
3 Principle
3 原理
3。1 A xenon arc， fitted with filters， is ud to simulate the relative spectral irradiance of daylight in the ultraviolet （UV) and visible regions of the spectrum.
3。1 配置了合适的滤光器的氙弧灯,其产生的辐射类似于地面日光的紫外和可见区的光谱
能量分布.
3。2 Specimens are expod to various levels of light， heat, relative humidity and water (e 3。4) under controlled environmental conditions.
3。2 将试样暴露于不同水平的光线，热度，相对湿度以及水淋等受控的环境条件下
3.3 The exposure conditions are varied by lection of
a) the light filter（s);
b） the irradiance level；
c） the temperature during exposure to light；
d) the relative humidity in the chamber during light and dark exposures, when exposure conditions requiring control of humidity are ud;
e） the way the test specimens are wetted （e 3。4)；
f） the water temperature and wetting cycle；
g） the relative lengths of the light and dark periods.
3。3 暴露的条件可有多种选择：
a)滤光器
b）辐射等级
进展英文
c)光照时的温度
d）当暴露条件要求控制湿度时,测试箱在日光及无光照射时的相对湿度
e）试样加湿的方式
f)水浴温度计加湿循环周期
增长率英文g)光照及非光照的周期时长
3.4 Wetting is produced by spraying the test specimens with demineralized/deionized water, by immersion in water or by condensation of water vapour onto the surfaces of the specimens。
试验片的加湿是通过喷射去矿物水/去离子水,浸入水中或在试样表面冷凝水汽来实现的.
3。5 The procedure includes measurements of the UV irradiance and UV radiant exposure in the plane of the specimens。
3。5 程序应包含测量试验片平面上受到的UV辐射度及UV辐射曝量。
3。6 It is recommended that a similar material of known performance （a control） be expod simultaneously with the test specimens to provide a standard for comparative purpos.
3.6 建议同时放置一个已知性能的材料用做测试样品的比对标准。
乐观英文3.7 Intercomparison of results obtained from specimens expod in different apparatus s
hould not be made unless an appropriate statistical relationship has been established between the apparatus for the particular material expod.
3。7 试样暴露于不同的装置得到的结果可相互比较，superior是什么意思
4 Apparatus
4.1 Laboratory light source 实验光源
deuce
4.1。1 General
2011年12月四级The light source shall compri one or more quartz-jacketed xenon—arc lamps which emit radiation from below 270 nm in the ultraviolet through the visible spectrum and into the infrared。
4.1.1 石英套管的氙弧灯的光谱范围包括波长大于270nm的紫外光、可见光和红外辐射
英语学习网
In order to simulate daylight, filters shall be ud to remove short—wavelength UV radiation （method A, e Table 1）. 女孩英语名字大全
为了模拟直接的自然暴露，辐射光源必须过滤，以便提供与地球上的日光相似的光谱能量分布（方法A，将表1）
Filters to minimize irradiance at wavelengths shorter than 310 nm shall be ud to simulate daylight through window glass （method B， e Table 2）.
采用可减少波长310nm以下光谱福照度的滤光器来模拟透过窗户玻璃绿光后的日光(方法B,见表2）
In addition, filters to remove infrared radiation may be ud to prevent unrealistic heating of the test specimens, which can cau thermal degradation not experienced during outdoor exposures.
总之,当加热试样对光化学反应速度有不利影响，或在自然暴露下并不会引起热老化时，可以使用附加的滤光器来减少非光化作用的红外能量.
NOTE Solar spectral irradiance for a number of different atmospheric conditions is described in CIE Publication No. 85。 The benchmark daylight ud in this part of ISO 48
92 is that defined in Table 4 in CIE No。 85:1989.
