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Measuring Hardness and Bursting Strength
Kholod K Salama1*, Mona F Ali2 and Said M El-Sheikh3
1National museum of Egyptian civilization, Cairo, Egypt
2Conservation Department, Faculty of Archaeology, Cairo university, Egypt
3Nano- Structured Materials and Nanotechnology Division, Advanced Materials Department, Egypt
Submission: July 28, 2018; Published: August 20, 2019
*Corresponding author: Kholod K Salama, National museum of Egyptian civilization, Cairo, Egypt
How to cite this article: Kholod K Salama, Mona F Ali, Said M El-Sheikh. Measuring Hardness and Bursting Strength for Paintings.
Glob J Arch & Anthropol. 2019; 10(3): 555789. DOI: 10.19080/GJAA.2019.10.555789
This paper presents a research results on using different nanomaterials such as (nano calcium hydroxide, nano calcium carbonate, nano silicon dioxide, magnetic nano wire, magnetic nanoparticles, carbon nano tube) then nanomaterials with polymeric material (Beva 371) soluble in toluene/ethanol. The authors have enhanced some existing experimental techniques for testing the effects of such nanomaterials in consolidation in laboratory, using means of tests on non-standard mockup models to identify the success of paintings consolidation treatment. Hardness was tested which express the painting resistance to be penetrated by shore D (Durometer) and that instrument doesn’t cause any damage to the surface as it can test the hardness in small inconspicuous place in the painting surface. Bursting strength which express the ability of paintings to bear pressure tested by Tinuis Olsen, that instrument must test mockup models not the original surface
Discussion the use of different nano materials in consolidation of mock up models of an Egyptian Coptic fresco painting, to compare the results in order to apply the final chosen nanomaterial on the original Coptic fresco painting, show new ways for Testing of consolidated samples and results using Durometer which can be used in small inconspicuous place in the painting surface without any damage to the sample or the original painting itself. And using Tinuis Olsen which must be used with models as the samples were broken after the test.
Many paintings suffered from weakness and fragility so consolidation process aimed to increase the resistance of paintings to the surroundings, previously it was well known that no tests can assure the success of consolidation material but now days mock up models are using as experimental models to get the final results which will be applied on the original monument. that important step in conservation filed need to be assured by testing the new characteristics in the treated models with different nanomaterials using the durometer to define the hardness and Tinuis Olsen to define the bursting strength. All nano materials are producing anew characteristics in the treated models .
All the chemicals were of analytical grade and were used without further purification. The nano- materials are nano-calcium hydroxide, nano-calcium carbonate, nano silica,
magnetic nano particles, magnetic nanowires, carbon nano
tube were obtained from nano tech com. LTD. and BEVA 371 is a thermoplastic, elastomeric polymer mixture. It is composed of Elvax (ethylenelvinyl acetate [EVA] copolymer), ketone resin N (polycyclohexanone), A-C copolymer (EVA), Cellolyn 21 (phthalate ester of hydroabietyl alcohol), and paraffin. It is an opaque gel at room temperature and has a melting point of 50-55 °C. It is soluble in naphtha, toluene, acetone, and alcohol. BEVA produces a matte , waxy finish and is used as a consolidated for paintings and textiles and it was purchased from Arts Conservation Agency (local company). Water was purified by a Millipore Elix 3 apparatus: the resistance of the ultra-pure water was 18 MΩ.cm.
The nanomaterial was sonicated in ultrasonic power 100 for 1 hour to make a homogenous suspension. Preparation of the mixed nanomaterial / system was carried out via backing of the
Coptic fresco paint with 2gm of nanomaterials dissolved in 98
ml of isopropanol at room temperature, then the nano-materials
suspension in polymeric material (Beva371) .
The models prepared according to the original mural
painting Which stored in the Coptic museum with registration
No 8425, it suffered from weakness as there are a vital crack. The
models cut in pieces to be tested after application of different
nano- materials (Figure 1).
Hardness: Hardness is expressing the strength of mural
paintings to the outside pressures, there are many discoloration
methods which causing a big hole in the surface but the Shore D
instrument is consider safety methods to test the hardness. As
the Shore D scale is based on ASTM D2240. The test involves the
use of a hardened steel rod 1.1mm - 1.4mm diameter, with a 30°
conical point, 0.1 mm radius tip. This exerts 44.64 N of force 
The measured hardness is determined by the penetration depth
of the indenter under the load maximum penetration for each
scale is 2.5- 2.54mm, the amount of penetration is converted
to hardness reading on scale of 100 units maximum hardness
value 100 shore corresponds to zero penetration which can be
converted in to newton to be 44.45 N in Table 1  (Figure 2).
*If the hardness 100 the length of indenter =0: The
consolidated samples tested by Dorometer in inconspicuous
place in the sample surface ,The hardness of Sample before
treatment in range 15-19 but after treatment and the application
of nano calcium hydroxide increase the hardness to 35-47 and
after application of nano calcium carbonate the hardness became
45 , with nano silica the hardness became 30, with magnetic
nano particles the hardness became 30-35 and the treatment
with carbon nanotube the hardness became 69 so there is an
improvement in hardness after treatment with nano-materials
(Figure 3) (Table 2).
Bursting Strength: The bursting strength is express the
ability of the mural paintings to bear the out pressure to be
broken so that test is revisable. Currently in this paper Tinuis
Olsen H5KT machine was designed for using in Research
and Quality Control to measure material’s strength and
performance. All tests are designed and implemented by Tinius
Olsen in accordance with key international testing standards
including ISO , ASTM, EN and other industrial standards. The
load measurement accuracy: +/- 0.5% of applied load from 2%
to 100%, and position measurement accuracy: +/- 0.01% of
reading or 0.001 mm  (Figure 4).
a. The pressure strength for the samples before treatment
in range 248-250 newton
b. The nano silica and calcium carbonate filled the gaps
inside the interior structure the bursting strength 300-400
c. Treated models with magnetic nano particles and
magnetic nano wires the bursting strength in range 300-350
d. The treated model with carbon nano tube the bursting
strength increased to 600-650.
e. The treated model with nano calcium hydroxide the
bursting strength improved to be in range 400-550 newton.
(Figure 5) (Table 3)
In studies of the behavior of nanomaterials in consolidation
mockup models prepared only to make a comparison under
specific conditions as Hardness and bursting strength. There
are a very wide range between sample before treatment and
after treatment with nanomaterials which proved that an
improvement happened in the treated models because of
nanomaterials which filled gaps, according to nano-calcium
hydroxide which combines with carbon dioxide forming calcium
Giorgi R, Baglioni M, Berti D, Baglioni P (2009) New Methodologies for the Conservation of Cultural Heritage: Micellar Solutions. Microemulsions, and Hydroxide Nanoparticles, Account of Chemical Research pp. 605-704.
Berger GA (1975) Heat-Seal Lining of a Torn Painting with BEVA 371. Studies in Conservation 20(3): 51-125.
Carretti E, Chelazzi D, Rocchigiani G, Baglioni P (2013) Interactions between Nanostructured Calcium Hydroxide and Acrylate Copolymers, Implications in Cultural Heritage Conservation pp. 9881-9890.
Kopeliovich D (2013) Requirements to engine bearing materials, www.substech.com.
Sližkova Z, Drdacky M (2014) Testing of treatment effects of nano sols on selected porous historic materials, Journal of Cultural Heritage p. 1- 4.