Process for the production of a sensitive plate for an exoelectron dosimeter

DETAILED DESCRIPTION The present invention relates to a process for carrying out the deposition of the mixture of the said substances on the plate, said deposition being in accordance with that described in the above-mentioned French patent application.
In general terms, the support on which the mixture of the substances having exoelectronic properties can be deposited comprises either a metallic member or a ceramic member.
For carrying out a deposition of this type, the following process has already been envisaged: The mixture of the two substances each having the properties defined hererinbefore and for example the mixture of the two types of alumina (.
alpha.
and .
beta.
) consits of making a pellet by means of the mixture of the two types of alumina and then performing fritting.
However, during this operation, there are difficulties due to the deterioration of the ionic conduction at temperatures close to 1000.
degree.
C.
However, normally fritting is carried out at temperatures of about 1600.
degree.
to 1800.
degree.
C.
It is admittedly possible to eliminate this problem by carrying out fritting in a carefully controlled sodium atmosphere, but nevertheless this process is very difficult to perform.
Therefore, the present invention relates to a process which is easier to perform and which nevertheless now makes it possible to effect this deposition of the mixture of substances on a plate, said deposit being solid, adheres well to the support and has interesting mechanical characteristics, without the fritting of the powder being necessary.
According to the invention, the process for producing a sensitive plate for an exoelectron dosimeter by making a deposit of a mixture of two compositions on a support comprises making a homogeneous mixture of the powders constituting the two compositions and the mixture of the powders is then sprayed by means of a device for spraying said mixture of two compositions by atomization to obtain a deposit wich adheres to the support.
According to a first way of carrying out said process a plasma jet is produced in the vicinity of the support on which the deposit is to be made by means of a plasma arc torch and said powder mixture in a pulverulent form is sprayed into said jet to obtain a deposit which adheres to the support