1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW3417 Natural Weathering Exposure Tests for Interior Trims/Materials Copyright 2011 General Motors Company All Rights Reserved November 2011 Originating Department: North American Engineering Standards Page 1 of 6 1 Scope Note: Nothing in this standa
2、rd supercedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 1.1 Purpose. This test procedure describes procedures for conducting natural weathering exposure tests to evaluate the exposure toleran
3、ce of interior automotive materials, components and assemblies. The tests are conducted in climatic regions which offer extreme solar environments. 1.2 Foreword. This test procedure was developed to create a common method for evaluating natural weathering. 1.3 Applicability. Not applicable. 2 Refere
4、nces Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ISO 105-A02 ISO 2813 2.2 GM Standards/Specifications. GMW6992 GMW14444 3 Resources 3.1 Facilities. 3.1.1 Test Location Area. Code L1 = Phoenix, Arizona, USA Code L2 = Miami
5、 or Southern Area, Florida, USA Code L3 = Juarez, Mexico Code L4 = Allunga, Queensland, Australia Code L5 = Cruz Alta, Brazil Code L6 = Okinawa, Japan 3.2 Equipment. 3.2.1 Solar Exposure Equipment. 3.2.2 Test Fixtures. Code F1 = High temperature limited, enclosed with operable vents, under glass, st
6、atic box. Code F2 = High temperature limited, enclosed with operable vents, under glass, tracking box. Code F3 = High temperature limited, enclosed with operable vents, under glass, static box with added water tray. Code F4 = High temperature limited, enclosed with operable vents, under glass, track
7、ing box with added water tray. Code F5 = Naturally ventilated, under glass, static rack. Code F6 = Special tests requiring some nonstandard test condition(s) may be used if all parameters are defined and agreed to. Prefer using for development purposes only. Copyright General Motors Company Provided
8、 by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3417 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 2 of 6 3.2.3 Glass Type. Code G1 = Clear tempere
9、d flat sheet glass, free of imperfections, with a thickness of 3 0.5 mm. Code G2 = Clear laminated glass incorporating a Dupont Butacyte, or equivalent automotive windshield laminate, with a thickness of 5.8 0.5 mm. 3.2.4 High Temperature Limits. Code T1 = Uncontrolled high temperature Code T2 = 77
10、C Code T3 = 85 C Code T4 = 93 C Code T5 = 102 C Code T6 = 110 C 3.2.5 The test fixtures should be located and spaced such that no fixture is significantly affected by shading or reflected radiation from another fixture or other object during daylight hours. 3.2.6 These test fixtures should face the
11、equator and be at an angle from the horizontal to help maximize solar exposure received throughout the year for the specific location. Report the angle used. 3.2.7 The fixtures should have sufficient interior volume to accommodate, when necessary, full assemblies such as instrument panels, consoles,
12、 door panels, and seat assemblies. 3.2.8 High temperature limiting fixtures (3.2.2 F1 to F4) should be equipped with a recirculating thermostatically controlled blower to prevent the temperature exceeding the specified maximum. The air recirculation system must be designed so that a uniform flow of
13、fixture interior air is directed across the reference black panel and the test specimen(s) surface from the rear toward the front of the fixture. The control system should turn the circulation on at the limit temperature and off at 3 C below the limit temperature. Note: High temperature limiting fix
14、tures must be equipped with over temperature protection in case of control system, blower, or power failure. This protection must activate at less than 6 C above the limit temperature. 3.2.9 Reference black panel shall be used to measure the fixture temperature. The measurement is taken on the back
15、surface of a black panel. The black panel shall be constructed of 0.60 0.06 mm thick sheet steel with dimensions of approximately 100 125 mm, primed and painted with black high heat spray paint. The panel to be mounted on approximately 13 mm thick black plywood with dimensions at least 110 135 mm wi
16、th a machined recess to allow space for a temperature sensor, thermocouple and their lead wires attached to the back of the black panel. The response of the temperature sensor must be such that its output does not lag the thermocouple by more than 3 C. 3.2.10 Pyranometers mounted at test fixture ang
17、le under test fixture glazing shall be capable of sensing incident solar radiation in 295 to 2800 nm wavelength range. Pyranometers shall be used with recording and data reduction equipment capable of providing hourly radiation measurements, at a minimum, and integrating over time to provide accumul
18、ated solar energy. This instrumentation must be stationary or azimuth tracking to match the test condition. 3.2.11 Ultraviolet (UV) radiometers mounted at test fixture angle under test fixture glazing shall be capable of sensing incident radiation in the 295 to 385 nm wavelength range. UV radiometer
19、s shall be used with recording and data reduction equipment capable of providing hourly radiation measurements, at a minimum and integrating over time to provide accumulated solar energy. This instrumentation must be stationary or azimuth tracking to match the test condition. 3.2.12 Ambient air temp
20、erature measuring equipment capable of recording temperatures hourly. 3.2.13 Ambient humidity measuring equipment capable of recording humidity measurements hourly. 3.2.14 Color Machine - Spectrophotometer capable of CIELAB measurements, with a ten degree standard observer, a D65 standard illuminate
21、 and an orifice size between 10 and 30 mm. The acceptable machine geometries are: 45 degree/normal (45/0) normal/45 degree (0/45) diffused/normal (d/0) normal/diffused (0/d) Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or net
22、working permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3417 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 3 of 6 If a diffused geometry instrument is used, the specular component of reflectance shall be included in the measurement. The ang
23、le between the sample normal and the illuminating beam in 0/d geometry, and the angle between the sample normal and the viewing beam in d/0 geometry, shall not exceed ten degrees. 3.2.15 Glossmeter - Capable of measuring the specular gloss on test specimen surfaces and complying with ISO 2813. 3.2.1
24、6 Gray Scale for Color Change ISO 105-A02. 3.2.17 Thermocouples and associated recording and data reduction equipment capable of providing temperature information of test specimens on an hourly basis at a minimum, when required. 3.3 Test Vehicle/Test Piece. Not applicable. 3.4 Test Time. The timing
25、will be set based on the material specification requirement in GMW14444. 3.5 Test Required Information. Not applicable. 3.6 Personnel/Skills. Not applicable. 4 Procedure 4.1 Preparation. 4.1.1 Test Material. Mounting frames such as a 13 mm thick plywood covered with white card stock. 4.2 Conditions.
26、 4.2.1 Environmental Conditions. The environmental conditions will be set based on the material specification requirement in GMW14444. 4.2.2 Test Conditions. Deviations from the requirements of this standard shall have been agreed upon. Such requirements shall be specified on component drawings, tes
27、t certificates, reports, etc. 4.3 Instructions. 4.3.1 Summary of Test Method. Test specimens of materials, components or assemblies are exposed under glass to natural sunlight in a climatic region which offers extreme high temperatures and sunlight exposures. The specimens are then rated for color a
28、nd degradation changes. 4.4 Test Sample Preparation. 4.4.1 Cut material test specimens to a size desired by the test requestor. For components or assemblies the whole part/system is tested. 4.4.2 Mount the test specimens to a mounting frame and secure to the sample shelf or the floor of the test fix
29、ture. Mounted test specimens shall be between 50 and 100 mm below the glass surface, and at least 150 mm from the left and right sides of the test fixture, and at least 100 mm from the top and bottom sides of the test fixture. 5 Data 5.1 Calculations. 5.1.1 Calculate the total solar radiation seen b
30、y the test specimen (at the test angle under the test glazing), in Langleys. This is optional for all high temperature limited test fixtures. 5.1.2 Calculate the total ultraviolet radiation seen by the test specimen at the test angle under the test glazing, in Langleys. This is optional for all high
31、 temperature limited test fixtures. 5.1.3 Define the daily high black panel temperature and average over the length of the test. This is not required for high temperature limited test fixtures. 5.1.4 For high temperature limited test fixture, calculate the total accumulated Temperature Normalized Ra
32、diation (TNR) Langleys test duration with the following formula. e n dst a rt )e*RT N R 2 7 3 .1 5 ) 5 0 0 0 /( T-( 1 3 .6 4 3 Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
33、GM WORLDWIDE ENGINEERING STANDARDS GMW3417 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 4 of 6 Where: TNR = Temperature Normalized Radiation (expressed in TNR Langleys) recorded on an hourly basis calculated with instantaneous temperature and irradiance (radiation int
34、ensity) sampled at 5 minute intervals. R = Solar Radiant Exposure (Langleys) accumulated hourly from irradiance values (radiation intensities) measured at the test angle under test glazing. Accumulated hourly radiation is calculated from irradiance sampled every 5 minutes and used as a representativ
35、e average during the 5 minute interval. T = Temperature (Centigrade) measured on the fixture reference black panel. Instantaneous temperatures measured every 5 minutes are used in the calculation to represent the average temperature of the 5 minute interval. Note: Formula normalized temperature is 9
36、3.3 C (200 F). 5.1.5 Perform periodic visual inspections, in natural daylight, of test specimen(s). Note the observations, comparing to a control if possible, for appearance or degradation changes. Note the radiation level (in Langleys and/or TNR Langleys) when the observations were made. Note: If a
37、rbitration is required, final assessment to be made in a light booth that complies with GMW6992. 5.1.6 Use the following rating scale when visually evaluating color change. Visual assessments to be made by a person with a trained eye. 10 = No Change. No hue or pattern change. No value change with a
38、gray scale reading of five. 8 = Slight Change. No hue or pattern change. Slight value change with gray scale reading of four or better. 6 = Noticeable Change. Slight hue and/or pattern change. Noticeable value change with a gray scale reading of three or better. 4 = Objectionable Change. Noticeable
39、hue and/or pattern change. Excessive value change with a gray scale reading of two or better. 2 = Severe Change. Excessive hue and/or pattern change. Severe value change with a gray scale reading of one or better. 5.1.7 Perform color and gloss measurements at specified intervals. Clean the test spec
40、imen of foreign matter such as dust or lint using a soft bristled brush or by wiping with a damp colorfast cloth, prior to making measurements. Use of soap is optional and its use should be declared on the report. Note the radiation level (in Langleys and/or TNR Langleys) when the measurements were
41、made. Calculate the differences between the unexposed control sample or the start of test values on the unexposed sample and the exposed test specimen. 5.2 Interpretation of Results. Not applicable. 5.3 Test Documentation. 5.3.1 For high temperature limiting test fixtures, position the air system ou
42、tlet the same distance below the glass as the test specimen surface. 5.3.2 Position the black panel, in the air stream if applicable, in the same plane as the test specimen surface. Connect the temperature sensor lead wires to the temperature controller and set the controller to the specified limit
43、temperature, if applicable. Connect the black panel monitoring thermocouple to the recorder. The black panel temperature must be recorded at least once per hour during fixture operation. 5.3.3 Expose the test specimen(s) to the natural light for an exposure level defined in the appropriate material
44、specification. 5.3.4 The test fixture glazing shall be cleaned on both sides, inside and out, once per month or more frequently if required. Care must be exercised to avoid getting cleaning solution on the test specimen(s). 6 Safety This standard may involve hazardous materials, operations, and equi
45、pment. This standard does not propose to address all the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Copyright General Motor
46、s Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3417 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 5 of 6 7 Report 7.1 Report the
47、 color change from visual evaluation. Note any appearance or degradation changes seen that are not included on the color change rating scale. 7.2 Report the color machine measurements for L, C, H, a, b for both the start of test and the end of test values, as well as any requested intervals. Report
48、the available delta values (DE, DL, DC, DH, Da, and Db). 7.3 Report the gloss meter measurements, if applicable. Note if a mild soap solution was used to clean test specimens prior to measurements. 7.4. Report the start of test and end of test dates. 7.5 Report the total solar radiation, in Langleys
49、, where applicable. 7.6 Report the total UV radiation, in Langleys, where applicable. 7.7 Report the total TNR, in TNR Langleys, where applicable. 7.8 Report the average high black panel temperature, or the high temperature limit of the high temperature limited test fixture, in C. 7.9 Report the test fixture angle from the horizontal. 7.10 Include the weather report for the entire test perio
