1、 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 1 of 2 NAVISTAR, INC. CEMS (CORPORATE ENGINEERING MATERIAL SPECI
2、FICATION) NUMBER: CEMS GT-23 TITLE: Determination Of Phosphate Coating Weight On Ferrous Substrate CURRENT ISSUE DATE: August 2009 WRITTEN/REVIEWED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES ISSUE OF: August 2001 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRE
3、NT REVISION This specification may involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropriate safety and health practices and to determine the applicability of
4、 regulatory limits prior to use. Change Notice: Replaced “International Truck and Engine Corporation” with “Navistar, Inc.” per corporate directive. 1.0 SCOPE This is a method for determining the amount (by weight) of phosphate coating on iron and steel parts by the chromic acid method. This method
5、can also be used to remove the phosphate coating to permit visual or microscopic examination of the substrate. 2.0 APPARATUS 2.1 Recirculating furnace capable of maintaining a temperature of 118+ 3C (245+ 5F). 2.2 Laboratory balance with accuracy of + 0.0001 gram. 2.3 Desiccator. 2.4 Glass thermomet
6、er capable of 71+ 3C (160+ 5F). 2.5 Laboratory hot plate with magnetic stirring capability. 2.6 Laboratory hood or exhaust cabinet to ensure that any potentially harmful acid vapors are not released into the laboratory atmosphere. 2.7 Teflon covered stirring magnets. 2.8 1000 ml graduate. 2.9 Glass
7、stoppered Erlenmeyer or Florence flask 1200-1500 ml capacity. 2.10 Pyrex beaker or porcelain lined tray suitable for immersing the test sample. 2.11 Chemical resistant forceps or equivalent. 2.12 Solvent resistant wash bottles. 3.0 MATERIAL 3.1 Chromium trioxide (CrO3) reagent grade, anhydrous. 3.2
8、Water, distilled. 3.3 Xylene, reagent grade. 3.4 Isopropyl alcohol, reagent grade. 3.5 Laboratory cleaning tissues. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: CEMS GT
9、-23 TITLE: Determination Of Phosphate Coating Weight On Ferrous Substrate CURRENT ISSUE DATE: August 2009 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability.
10、 2009 Navistar, Inc. AUGUST 2009 Page 2 of 2 4.0 PREPARATION OF CHROMIC ACID 4.1 Weigh out 200 + 0.5 g of chromium trioxide and transfer into a flask. 4.2 Transfer the flask and laboratory hot plate to the exhaust hood. 4.3 Add 300-500 ml of distilled water and adjust magnetic stirrer to a steady me
11、dium action. 4.4 Adjust the temperature to approximately 60C(140F) while stirring the solution. 4.5 Slowly add the distilled water to make 1 liter and continue stirring for approximately 5 minutes. 4.6 Cool the solution to room temperature. The stock solution so prepared is a 20% chromic acid with a
12、 specific gravity of 1.160-1.165. Caution: Disposition of waste chromic acid solution may be regulated by local EPA requirements. Warning: Chromic acid is an oxidizer and must not be brought into contact with reducing agents, organic compounds, or solvents. 5.0 PROCEDURE 5.1 Degrease the test specim
13、en with xylene and dry with isopropyl alcohol. Sample must be clean. Excess grease or oil may require additional cleaning. 5.2 Dry the sample in a recirculating oven at 118+ 3C (245+ 5F). 5.3 Cool the sample in a desiccator to room temperature and weigh the sample to the nearest 0.0001 gram. 5.4 Pou
14、r sufficient chromic acid solution into a suitable beaker or porcelain lined tray to completely immerse the test sample. 5.5 Place the container on the hot plate in the exhaust hood and carefully heat to a temperature of 77+ 3C (170+ 5F). 5.6 When temperature equilibrium is attained, immerse the tes
15、t sample in the acid solution for a period of three (3) minutes. 5.7 After three (3) minutes, carefully remove the test specimen from the acid and thoroughly rinse the sample with distilled water and with isopropyl alcohol. 5.8 Dry the specimen in a recirculating oven at 118+ 3C (245+ 5F) for five m
16、inutes. 5.9 Cool the sample to room temperature in a desiccator and weigh to the nearest 0.0001 gram. 5.10 Record the difference in weight between Steps 3 and 9 in milligrams. The weight divided by the total surface area (on both sides) of the sample, in square feet or square meters, is the coating weight per unit area of surface. 6.0 REPORT Report the coating weight in mg/ft2 or mg/m2. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
