EXAMPLE OF ANALYSIS REPORT
SAMPLES OF GRANITES
TYPES | Class | Hardness Shore mininmum | Average | Maximum | |
1- BIANCO UNIVERSAL | 3 | 93,6 | 95,6 | 101,8 | |
2- GALAXY SILVER | 1 | 96,2 | 80,6 | 94,3 | |
3- CAPAO BONITO | 4 | 23,3 | 83,9 | 104,7 | |
4- BIANCO SARDO | 3 | 74,1 | 92,7 | 102,0 | |
5- GREEN TWEED | 2 | 86,2 | 96,4 | 105,8 | |
6- BIANCO CECILIA | 3 | 81,6 | 94,5 | 106,2 | |
7- EAGLE RED | 4 | 73,1 | 95,3 | 104,1 | |
8- ROSA MINHO | 4 | 81,0 | 95,1 | 101,9 | |
9- VERDE MARE | 2 | 55,9 | 82,8 | 94,4 | |
10- KOYU LABRADOR | 2 | 69,0 | 85,4 | 94,2 |
Samples n° 3 and n° 9 are not homogenous materials. Sample n°9 in particular showed big grains made of quartz.
SAMPLES OF SEGMENTS
1. Analysis:
Segments are made of Cu xx %, Fe yy % and Co zz %. This is conform to the analysis you gave us.
2. Metallography:
On the SEM picture enclosed, you will clearly observe that the addition of carbonyl iron has not diffused in the matrix. This is most probably due to a low sintering temperature.
The carbonyl iron is spherical and we can clearly see the border of the grains (see the dark grey spots on the picture).
On the contrary, the probability exists that carbonyl iron particles were subject to high oxidization.
Conclusion: the addition of carbonyl iron was not necessary.
3. Working Surface:
One can clearly see on the SEM pictures that the working surface of the segments looks normal. The number of “pulls-out” looks normal too.
But, we can clearly observe that the diamonds have a strong tendance to polish. This mainly explains why the discs stopped cutting after a while.
4. Diamonds:
5 segments were disolved into acid baths and diamonds have been submitted to an extra-cleaning.
The concentration is about C19. The size of the diamonds is clearly a 50/60 Mesh. Diamonds 60/70 Mesh are not found.
CONCLUSIONS
As a first step, we would recommend a matrix made of 97-98%wt of BOND Y and of 2-3% of Nickel Coated Graphite.
To this extent, you should first add 1%wt only of Nickel coated graphite for test purposes and then increase its contents to 2%wt and then 3%wt after you have received the results from your customers. Do not exceed 5% in volume of Nickel coated graphite.
Concerning the diamonds quality, we would advise the use of FOX 1185 50/60 Mesh at a concentration C20.
The sintering temperature should be the same at 720 °C for 3-5 minutes.
As agreed, we will immediately send you a sample of 50 cts of FOX 1185 50/60 for test purposes on one blade.