Material Characterization of PMC/TBC Composite Under High Strain Rates and Elevated Temperatures

Abstract

Polymer matrix composites (PMC), despite their many advantages, have limited use at elevated temperatures. To expand the scope of their uses, it becomes necessary to use thermal barrier coatings (TBC). In addition to elevated temperatures, composite structures, and thus TBC barriers, can be exposed to damage from impacts of foreign objects. Therefore, before using the thermal barrier in practice, knowledge about its behavior under high-speed loads is necessary. The paper presents results for samples with the PMC/TBC system subjected to dynamic compression using a split Hopkinson pressure bar (SHPB). The substrate was made of CFRP (carbon reinforced polymer) with epoxy matrix and twill fabric. TBC was made of ceramic mat saturated by commercial hardener from Vitcas company. The tests were carried out at ambient temperature and elevated temperature—55 °C and 90 °C. Tests at ambient temperature were carried out for three pressure levels: 1, 1.5, and 2 bar. Only the pressure of 1 bar was used for the elevated temperature. Studies have shown that the limit load is 1 bar for ambient temperature. At 1.5 bar, cracks occurred in the TBC structure. Increased temperature also adversely affects the TBC barrier strength and it is damaged at a pressure of 1 bar.

Comparison of Numerical Simulation Techniques of Ballistic Ceramics under Projectile Impact Conditions

“…where: p HEL = pressure for the yield point of Hugoniot; σ HEL = stress for the actual yield point of Hugoniot; A J-H = strength constant of the intact material; N J-H = strength exponent of the intact material; C J-H = strain rate constant; B J-H = strength constant of the damaged material; M J-H = strength constant of the damaged material; D 1 and D 2 = the constant and the exponent of failure respectively. The data for the numerical models were taken from the literature and from our own library of materials developed on the basis of our own research characterizing the materials [41][42][43][44][45][46]. The list of applied parameter values is presented in Tables 3 and 4.…”

“…The data for the numerical models were taken from the literature and from our own library of materials developed on the basis of our own research characterizing the materials [ 41 , 42 , 43 , 44 , 45 , 46 ]. The list of applied parameter values is presented in Table 3 and Table 4 .…”

Statistical homogenization of polycrystal composite materials with thin interfaces using virtual element method

“…Step 5 Compute: evaluate the average bulk modulus, K δ , the relative standard deviation σ( K δ ) and variation coefficient CV ( K δ ). Then com- 2 , which ensures that the confidence interval of the average homogenized constitutive parameter set at 95%, evaluated over the normal standard distribution, is within the tolerance allowed, T ol. Repeat Steps 3-4 until N i < N lim .…”

“…Modern composites materials are conceived to fulfil specific design requirements calling for the need of materials with increasingly high performances in terms of stiffness, strength, fracture toughness and lightness, among others. Special attention has been devoted in the last decades to advanced ceramics, namely composites with ceramic (CMC) or metal matrix (MMC) [1,2] which are gradually more used for a wide range of challenging applications, ranging from bioengineering, with the production of biocompatible ceramics for prosthesis and artificial organs [3], aerospace, defence, automotive [4] up to mechanical engineering for the production of wearing parts, seals, low weight components and fuel cells, and cutting tools with distinguished thermo-mechanical and wear properties [5]. Often ceramic composites exhibit a peculiar microstructure, characterized by polycrystals interconnected by a second-phase interphase of small thickness in comparison to the grain diameter.…”

Technological and Strength Aspects of Layers Made of Different Powders Laminated on a Polymer Matrix Composite Substrate

“…In 2014, this proportion changed, and the use of aluminum dropped to 20% while there was an increase in the use of composites of up to 52%. However, further expansion of PMCs is limited due to their properties, such as low resistance to elevated temperatures and fire, low erosion resistance, and tendency to cracking and delamination under quasi-static or dynamic loading [1,2]. Such disadvantages can be eliminated to some extent by applying various multifunctional coatings on their surface.…”