This document is to be considered as a whole, the parts of which shall not be separated.

"Seul le texte français fait foi, les traductions n'étant faites que pour en faciliter l'emploi".

"The French text alone is valid. The translations are provided to assist the reader in understanding the

standards".

© RENAULT 2002.

No duplication permitted without the consent of the issuing department.

No circulation permitted without the consent of RENAULT.

DATE OF ISSUE

May 1999 - - - This issue originates from Draft NC 1999 0219 / - - A

REVISIONS

October 2001 - - A Complete revision, the test piece or part sections are from now on

dealt with in draft Standards 2001 0527 and 2001 0528.

This issue originates from Draft NC 2001 0535 / - -

June 2002 - - B Paragraphs 3., 4., 5., 6., 7. and annexes 2. and 2.2. modified.

This issue originates from Draft NC 2002 0242 / - - -.

1.  SCOPE AND FIELD OF APPLICATION

This test method is intended to describe a cycle of the cyclic corrosion test 1 (Essai de Corrosion

Cyclique 1: ECC1) on the associated equipment and the verifications which are necessary to make

sure that the test is in conformity.

This method may be applied to laboratory test pieces, to parts, or samples of vehicle parts.

2.  PRINCIPLE

The test pieces and/or parts are placed in an automatic corrosion chamber where they are exposed to

a succession of attacks in controlled atmospheres, which simulate natural contamination by chloride

ions, exposure to hot and humid atmosphere, and hot and dry atmosphere conditions.

3.  APPARATUS AND REAGENTS

3.1.  AUTOMATIC CORROSION CHAMBER

This chamber shall make it possible to program the phases described below and to alternate them:

NOTE: All these phases shall be performed at a controlled temperature of 35°C±0,8°C; their

durations shall be programmable.

3.1.1.  Contamination phase with spraying of saline solution

The machine design shall make it possible to adjust the spray homogeneity and to obtain a rain

quantity of 5 ml/h±1 ml/h at all points of the vat with the chamber empty or loaded.

The pressure is between 0,7 bar and 1,6 bar.

Moreover, in order to check that the salt spray phase has effectively taken place, the chamber shall

be fitted with a system used to check the flow rate and total consumption of the saline solution.

3.1.2.  Controlled humidity and drying phase

The hygrometry shall be variable between 20 % and 95 % relative humidity with a constant air flow

rate according to the profile defined in annex 1.

The accepted tolerance is±3 % relative humidity, except for the 20 % relative humidity point where

the accepted tolerance is±5 %.

3.1.3.  Flushing phase

This air flushing phase shall make it possible to eliminate the spray present in the chamber at the end

of the saline solution spraying phase.

3.1.4.  Wall rinsing phase

This phase consisting in rinsing the chamber walls with de-mineralised water makes it possible to

eliminate the salts deposited during the saline solution spraying phase and thus prevents the

accumulation and therefore the concentration of salts during the cycles, which has an influence on the

relative humidity profile. This is done with a rinsing pipe with nozzles located on the circumference of

the vat. No spraying of de-mineralised water on the parts or test pieces is allowed.

3.1.5.  Chamber environment

-  This chamber shall be continuously connected to a saline solution tank. Use of a vat of limited

capacity is recommended (to avoid solution variations: pH, Cl%).

The vat shall be designed in such a way that it can be easily cleaned. Improper cleaning entails

high flow drops, and therefore has an influence on the final quality of the test.

This vat shall be made from a material which does not influence the pH (e.g. PVC), and shall be

opaque to prevent bacteria and algae development during the test, which entails a degradation

of the saline solution.

-  If the saline solution is prepared in the vat, the latter shall be fitted with a shaker which does not

react to the saline solution (example: stainless steel shaker covered with a plastic sheath).

The outlet of the vat shall be fitted with a filter to prevent any possible contamination of the

circuit and therefore avoid the risk of blocking the sprayers.

-  The air entering the machine shall be de-oiled and filtered beforehand to avoid the presence of

particles. This air has the following qualification:

.  Filtered dry air free of water, oil,

.  metallic or organic particles, impurities less than 0.2 mg/m 2 and diameter less than 5 µm.

-  The water supply to the air humidifier and humidifier shall be de-ionised and have a minimum

resistivity of 200 000 Ohms.

3.2.  HOLDERS

The test piece holders shall be entirely made from a material which is incorruptible under the test

conditions (for example, PVC) and shall make it possible to incline the test pieces an/or parts

by 20±5°with respect to the vertical.

They shall be designed so as to avoid water retention areas.

Moreover, it is very important that these holders be made so as not to interfere with the air flow in the

chamber; therefore, it is necessary that all the PVC parts are hollowed to the maximum.

Any streaming down the holders (for example, emanating from the water retention on the solution and

air feed pipes, the wall rinsing, etc.) shall be avoided.

The test pieces shall be positioned on a single level (for 9 cm x 19 cm test pieces) and be at a

sufficient height to let the air flow in the chamber.

NOTE: it is important for the quality of the test not to overload the chamber (identical profile

relating to the relative humidity and volume of saline solution received by each test piece).

Example: maximum 110 samples 9 cm x 19 cm for a vat capacity of 1 200 litres.

3.3.  SODIUM CHLORIDE

In the anhydrous state, the sodium chloride shall not contain more than 0,2 % of total impurities and

more than 0,1 % of sodium iodide.

3.4.  PH-METER (minimum accuracy 0,1 pH).

3.5.  SULPHURIC ACID 0,5 mol/l (1 N).

4.  SOLUTION PREPARATION

It is preferable to prepare a new solution before each test, and not prepare more than 50 litres at a

time for each chamber to avoid any changes in it over time.

NOTE: For chambers, the volume of which is greater than 3 m 3 , the volume of saline solution to be

prepared is left to the judgement of the users.

The solution which is sprayed during this test is a 1 % Na Cl, pH4 solution.

The solution is prepared before each test according to the following steps:

-  prepare the desired quantity of de-mineralised water (resistivity greater than 200 000 Ohms),

-  start the paddle,

-  add the quantity of salt which is calculated; the final solution is 1±0,05 % NaCl (10±0,5 g/l),

-  when the salt has dissolved, wait for 4 hours minimum, then adjust the pH of the solution

to 4,0±0,2 with sulphuric acid 1 N.

To validate the salt concentration of the solution, the density is measured and recorded whenever the

solution is prepared.

It shall be between 1.0065 and 1.0075 (at 25°C).