1
|
Chaves YS, Monteiro SN, Nascimento LFC, Rio TGD. Mechanical and Ballistic Properties of Epoxy Composites Reinforced with Babassu Fibers ( Attalea speciosa). Polymers (Basel) 2024; 16:913. [PMID: 38611171 PMCID: PMC11013200 DOI: 10.3390/polym16070913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 02/27/2024] [Accepted: 03/20/2024] [Indexed: 04/14/2024] Open
Abstract
The mechanical and ballistic performance of epoxy matrix composites reinforced with 10, 20, and 30 vol.% of babassu fibers was investigated for the first time. The tests included tension, impact, and ballistic testing with 0.22 caliber ammunition. The results showed an improvement in tensile strength, elastic modulus, and elongation with the addition of babassu fiber, and the 30 vol.% composite stood out. Scanning electron microscopy analysis revealed the fracture modes of the composites, highlighting brittle fractures in the epoxy matrix, as well as other mechanisms such as fiber breakage and delamination in the fiber composites. Izod impact tests also showed improvement with increasing babassu fiber content. In ballistic tests, there was an increase in absorbed energy. All composites surpassed plain epoxy by over 3.5 times in ballistic energy absorption, underscoring the potential of babassu fiber in engineering and defense applications.
Collapse
Affiliation(s)
- Yago Soares Chaves
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tíburcio, 80, Urca, Rio de Janeiro 222290-270, Brazil; (S.N.M.); (L.F.C.N.)
| | - Sergio Neves Monteiro
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tíburcio, 80, Urca, Rio de Janeiro 222290-270, Brazil; (S.N.M.); (L.F.C.N.)
| | - Lucio Fabio Cassiano Nascimento
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tíburcio, 80, Urca, Rio de Janeiro 222290-270, Brazil; (S.N.M.); (L.F.C.N.)
| | - Teresa Gómez-del Rio
- Durability and Mechanical Integrity of Structural Materials Group (DIMME), School of Experimental Science and Technology, Rey Juan Carlos University, Mostoles, 28933 Madrid, Spain;
| |
Collapse
|
2
|
Colorado HA, Yuan W, Meza J, Jaramillo F, Gutierrez-Velasquez EI. Enhancing Thermomechanical Strength and Thermal Stability of Poly(dicyclopentadiene) Composites through Cost-Effective Fly Ash Reinforcement for Structural and Impact Applications. Polymers (Basel) 2023; 15:4418. [PMID: 38006142 PMCID: PMC10675529 DOI: 10.3390/polym15224418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/11/2023] [Accepted: 10/15/2023] [Indexed: 11/26/2023] Open
Abstract
Poly(dicyclopentadiene) (poly-DCPD) is a thermoset with potential for high-performance applications. In this research, epoxy resin was blended with different concentrations of fly ash class F particles at 0.0, 1.0, 10.0, and 50.0 wt.%, aiming to improve its use as a high-volume structural material by decreasing costs and reducing its negative environmental impact through using fly ash particles. A planetary Thinky mixer was used to initially mix the resin with the curing agent, followed by incorporating a Grubbs catalyst. The microstructures were analyzed using scanning electron microscopy (SEM), where particles were found to be homogeneously distributed over the polymer matrix. The thermomechanical behavior was evaluated via curing, compression, dynamic mechanical analysis (DMA), and thermo-gravimetric analysis (TGA). Nanoindentation tests were also conducted. Fly ash was found to decelerate the curing of the resin through the release of calcium ions that enhanced the exothermic reaction.
Collapse
Affiliation(s)
- Henry A. Colorado
- Composites Laboratory, Engineering School, Universidad de Antioquia (UdeA), Calle 70 No. 52-21, Medellín 050010, Colombia
| | - Wei Yuan
- Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095, USA;
| | - Juan Meza
- Universidad Nacional de Colombia, Calle 75 No 79A 51, Bloque M17, Medellín 050032, Colombia;
| | - Franklin Jaramillo
- Centro de Investigación, Innovación y Desarrollo de Materiales—CIDEMAT, Facultad de Ingeniería, Universidad de Antioquia (UdeA), Calle 62 No. 52-59, Medellín 050010, Colombia;
| | | |
Collapse
|
3
|
Oliveira MS, Pereira AC, Colorado HA, Meliande NM, da Cunha JDSC, Figueiredo ABHDS, Monteiro SN. Thermal and Colorimetric Parameter Evaluation of Thermally Aged Materials: A Study of Diglycidyl Ether of Bisphenol A/Triethylenetetramine System and Fique Fabric-Reinforced Epoxy Composites. Polymers (Basel) 2023; 15:3761. [PMID: 37765616 PMCID: PMC10536536 DOI: 10.3390/polym15183761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 08/29/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
The main modifications of thermal and colorimetric parameters after thermal aging of DGEBA/TETA system (plain epoxy) and fique-fiber woven fabric-reinforced epoxy composites are described. As a preliminary study, thermal analysis was carried out on epoxy matrix composites reinforced with 15, 30, 40 and 50% fique-fiber woven fabric. After this previous analysis, the 40% composite was chosen to be thermally aged, at 170 °C. Three exposure times were considered, namely, 0, 72, 120 and 240 h. Samples were studied by thermogravimetric analysis (TGA), differential thermal analysis (DTA), differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and colorimetry analysis. Significant color changes were observed after thermal aging combined with oxidation. It was also found that the thermal behavior of the plain epoxy showed greater resistance after thermal exposure. By contrast, the composites were more sensitive to temperature variations as a result of thermal stresses induced between fique fibers and the epoxy matrix.
Collapse
Affiliation(s)
- Michelle Souza Oliveira
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil; (A.C.P.); (N.M.M.); (J.d.S.C.d.C.); (A.B.-H.d.S.F.); (S.N.M.)
| | - Artur Camposo Pereira
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil; (A.C.P.); (N.M.M.); (J.d.S.C.d.C.); (A.B.-H.d.S.F.); (S.N.M.)
| | - Henry Alonso Colorado
- CComposites Laboratory, Universidad de Antioquia UdeA, Street 70, n° 52-21, Medellin 050010, Colombia;
| | - Natalin Michele Meliande
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil; (A.C.P.); (N.M.M.); (J.d.S.C.d.C.); (A.B.-H.d.S.F.); (S.N.M.)
- Modeling, Metrology, Simulation and Additive Manufacture Section, Brazilian Army Technology Center-CTEx, Avenida das Américas, 28.705, Guaratiba, Rio de Janeiro 23020-470, Brazil
| | - Juliana dos Santos Carneiro da Cunha
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil; (A.C.P.); (N.M.M.); (J.d.S.C.d.C.); (A.B.-H.d.S.F.); (S.N.M.)
- Department of Polymeric Materials, Federal University of Amazonas, Avenue General Rodrigo Octavio Jordão Ramos, 1200, Manaus 69067-005, Brazil
| | - André Ben-Hur da Silva Figueiredo
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil; (A.C.P.); (N.M.M.); (J.d.S.C.d.C.); (A.B.-H.d.S.F.); (S.N.M.)
| | - Sergio Neves Monteiro
- Department of Materials Science, Military Institute of Engineering-IME, Praça General Tibúrcio, 80, Urca, Rio de Janeiro 22290-270, Brazil; (A.C.P.); (N.M.M.); (J.d.S.C.d.C.); (A.B.-H.d.S.F.); (S.N.M.)
| |
Collapse
|
4
|
Marchi BZ, da Silveira PHPM, Bezerra WBA, Nascimento LFC, Lopes FPD, Candido VS, da Silva ACR, Monteiro SN. Ballistic Performance, Thermal and Chemical Characterization of Ubim Fiber ( Geonoma baculifera) Reinforced Epoxy Matrix Composites. Polymers (Basel) 2023; 15:3220. [PMID: 37571114 PMCID: PMC10421134 DOI: 10.3390/polym15153220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 07/21/2023] [Accepted: 07/26/2023] [Indexed: 08/13/2023] Open
Abstract
The search for unexplored natural materials as an alternative to synthetic components has driven the development of novel polymeric composites reinforced with environmentally-friendly materials. Natural lignocellulosic fibers (NLFs) have been highlighted as potential reinforcement in composite materials for engineering applications. In this work, a less known Amazonian fiber, the ubim fiber (Geonoma baculifera), is investigated as a possible reinforcement in epoxy composites and was, for the first time, thermally characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Additionally, its chemical structure was elucidated by Fourier transform infrared spectroscopy (FTIR). Ballistic tests were also performed against the threat of a 7.62 mm high-speed lead projectile. The results were statistically analyzed by the Weibull statistical analysis method. FTIR analysis showed the functional groups normally found for NLFs highly rich in cellulose, hemicellulose, and lignin. The TGA/DTG results showed the onset of thermal degradation for the composites (325~335 °C), which represents better thermal stability than isolated ubim fiber (259 °C), but slightly lower than that of pure epoxy (352 °C). The DSC results of the composites indicate endothermic peaks between 54 and 56 °C, and for the ubim fibers, at 71 °C. Ballistic tests revealed higher energy absorption in composites with lower fiber content due to the more intense action of the brittle fracture mechanisms of the epoxy resin, which tended to dissipate more energy. These failure mechanisms revealed the presence of river marks, cracks, and broken fibers with a detachment interface. These results may contribute to the production of ubim fiber-reinforced composites in engineering applications, such as ballistic armors.
Collapse
Affiliation(s)
- Belayne Zanini Marchi
- Military Institute of Engineering, IME, Praça General Tibúrcio 80, Urca, Rio de Janeiro 22290-270, Brazil; (P.H.P.M.d.S.); (W.B.A.B.); (L.F.C.N.); (S.N.M.)
| | | | - Wendell Bruno Almeida Bezerra
- Military Institute of Engineering, IME, Praça General Tibúrcio 80, Urca, Rio de Janeiro 22290-270, Brazil; (P.H.P.M.d.S.); (W.B.A.B.); (L.F.C.N.); (S.N.M.)
| | - Lucio Fabio Cassiano Nascimento
- Military Institute of Engineering, IME, Praça General Tibúrcio 80, Urca, Rio de Janeiro 22290-270, Brazil; (P.H.P.M.d.S.); (W.B.A.B.); (L.F.C.N.); (S.N.M.)
| | - Felipe Perissé Duarte Lopes
- Laboratory for Advanced Materials—LAMAV, State University of North Fluminense, UENF, Campos dos Goytacazes 28013-602, RJ, Brazil;
| | - Verônica Scarpini Candido
- Materials Science and Engineering, Federal University of Para, UFPA, Highway BR-316, km 7.5–9.0, Ananindeua 67000-000, Brazil; (V.S.C.); (A.C.R.d.S.)
| | - Alisson Clay Rios da Silva
- Materials Science and Engineering, Federal University of Para, UFPA, Highway BR-316, km 7.5–9.0, Ananindeua 67000-000, Brazil; (V.S.C.); (A.C.R.d.S.)
| | - Sergio Neves Monteiro
- Military Institute of Engineering, IME, Praça General Tibúrcio 80, Urca, Rio de Janeiro 22290-270, Brazil; (P.H.P.M.d.S.); (W.B.A.B.); (L.F.C.N.); (S.N.M.)
| |
Collapse
|
5
|
Du J, Pu C, Sun X, Wang Q, Niu H, Wu D. Preparation and Interfacial Properties of Hydroxyl-Containing Polyimide Fibers. Polymers (Basel) 2023; 15:polym15041032. [PMID: 36850315 PMCID: PMC9967378 DOI: 10.3390/polym15041032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/23/2023] [Accepted: 01/26/2023] [Indexed: 02/22/2023] Open
Abstract
Developing polyimide (PI) fibers with excellent interfacial adhesion and high mechanical properties for the PI fiber-reinforced polymer matrix composites (PFRPs) industry has been challenging. In this work, 4,4'-diamino-(1,1'-biphenyl)-3,3'-diol (HAB) diamine was introduced into the rigid molecular chains, and the high-performance PI fibers, presenting an interfacial shear strength (IFSS) value of 46.33 MPa, tensile strength of 2.62 GPa, and modulus of 100.15 GPa, were successfully manufactured when the content of HAB in mixed diamines was 30 mol %. Fourier transform infrared (FTIR) spectroscopy identified the presence of intermolecular H-bonding interactions, and 2D small-angle X-ray scattering indicated that the introduction of HAB moiety contributed to reducing the radii of microvoids in the fibers, which were considered to be the key factors leading to a significant enhancement in the mechanical properties of the fibers. X-ray photoelectron spectroscopy (XPS) and the static contact angle intuitively illustrated that the synthetic fiber surface contained active hydroxyl groups. The IFSS value of PI fiber/epoxy resin composites (PI/EPs) was 56.47 MPa when the content of HAB reached 70 mol %. Failure morphologies confirmed that the interfacial adhesion of PI/EPs was enhanced owing to the surface activity of PI fibers. Consequently, this study provides an effective strategy to the long-standing problems of high mechanical performances and poor surface activity for traditional PI fibers used in the PFRPs industry.
Collapse
|
6
|
Ribeiro MP, da Silveira PHPM, de Oliveira Braga F, Monteiro SN. Fabric Impregnation with Shear Thickening Fluid for Ballistic Armor Polymer Composites: An Updated Overview. Polymers (Basel) 2022; 14:polym14204357. [PMID: 36297935 PMCID: PMC9611053 DOI: 10.3390/polym14204357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/07/2022] [Accepted: 10/12/2022] [Indexed: 11/07/2022] Open
Abstract
As destructive power of firearms raises over the years, ballistic armors are in continuous need of enhancement. For soft armors, this improvement is invariably related to the increase of stacked layers of high-strength fiber fabrics, which potentially restrains wearer mobility. A different solution was created in the early 2000s, when a research work proposed a new treatment of the ballistic panels with non-Newtonian colloidal shear thickening fluid (STF), in view of weight decreasing with strength reinforcement and cost-effective production. Since then, databases reveal a surge in publications generally pointing to acceptable features under ballistic impact by exploring different conditions of the materials adopted. As a result, several works have not been covered in recent reviews for a wider discussion of their methodologies and results, which could be a barrier to a deeper understanding of the behavior of STF-impregnated fabrics. Therefore, the present work aims to overview the unexplored state-of-art on the effectiveness of STF addition to high-strength fabrics for ballistic applications to compile achievements regarding the ballistic strength of this novel material through different parameters. From the screened papers, SiO2, Polyethylene glycol (PEG) 200 and 400, and Aramid are extensively being incorporated into the STF/Fabric composites. Besides, parameters such as initial and residual velocity, energy absorbed, ballistic limit, and back face signature are common metrics for a comprehensive analysis of the ballistic performance of the material. The overview also points to a promising application of natural fiber fabrics and auxetic fabrics with STF fluids, as well as the demand for the adoption of new materials and more homogeneous ballistic test parameters. Finally, the work emphasizes that the ballistic application for STF-impregnated fabric based on NIJ standards is feasible for several conditions.
Collapse
Affiliation(s)
- Matheus Pereira Ribeiro
- Department of Materials Science, Military Institute of Engineering—IME, Praça General Tibúrcio 80, Urca, Rio de Janeiro 22290-270, Brazil
- Correspondence:
| | | | - Fábio de Oliveira Braga
- Department of Civil Engineering, Federal Fluminense University—UFF, Niterói 24210-240, Brazil
| | - Sergio Neves Monteiro
- Department of Materials Science, Military Institute of Engineering—IME, Praça General Tibúrcio 80, Urca, Rio de Janeiro 22290-270, Brazil
| |
Collapse
|
7
|
Water Immersion Aging of Epoxy Resin and Fique Fabric Composites: Dynamic-Mechanical and Morphological Analysis. Polymers (Basel) 2022; 14:polym14173650. [PMID: 36080724 PMCID: PMC9459994 DOI: 10.3390/polym14173650] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/21/2022] [Accepted: 08/24/2022] [Indexed: 11/30/2022] Open
Abstract
Fiber-reinforced composites are among the most investigated and industrially applied materials. Many studies on these composites using fibers, especially with natural fibers, were made in response to an urgent action for ambient preservation. A particularly relevant situation exists nowadays in the area of materials durability. In this respect, no studies on water-immersion-accelerated aging in fique fiber–epoxy composites are reported. This work aimed to fill this gap by investigating the epoxy matrix composites reinforced with 40 vol% fique fabric. The epoxy matrix and the composite, both unaged and aged, were characterized by weight variation, water absorption, morphology, colorimetry (CIELAB method), Fourier transform infrared spectroscopy (FTIR) and dynamic–mechanical analysis (DMA). The main results were that degradation by water presents appearance of complex microfibril structures, plasticization of epoxy resin, and debonding of the fique fiber/epoxy matrix. The most intense color change was obtained for the water-immersion-aged epoxy by 1440 h. Cole–Cole diagrams revealed the heterogeneity of the materials studied.
Collapse
|
8
|
Dynamic and Ballistic Performance of Uni- and Bidirectional Pineapple Leaf Fibers (PALF)-Reinforced Epoxy Composites Functionalized with Graphene Oxide. Polymers (Basel) 2022; 14:polym14163249. [PMID: 36015506 PMCID: PMC9412585 DOI: 10.3390/polym14163249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/03/2022] [Accepted: 08/05/2022] [Indexed: 12/04/2022] Open
Abstract
Replacing synthetic fibers with natural ones as reinforcement in polymeric composites is an alternative to contribute to sustainability. Pineapple leaf fibers (PALF) have specific mechanical properties that allow their use as reinforcement. Further, graphene oxide (GO) has aroused interest due to its distinctive properties that allow the improvement of fiber/matrix interfacial adhesion. Thus, this work aimed to evaluate the ballistic performance and energy absorption properties of PALF-reinforced composites, presenting different conditions (i.e., GO-functionalization, and variation of fibers volume fraction and arrangement) through residual velocity and Izod impact tests. ANOVA was used to verify the variability and reliability of the results. SEM was employed to visualize the failure mechanisms. The Izod impact results revealed a significant increase in the absorbed energy with the increment of fiber volume fraction for the unidirectional configuration. The ballistic results indicated that the bidirectional arrangement was responsible for better physical integrity after the projectile impact. Furthermore, bidirectional samples containing 30 vol.% of GO non-functionalized fibers in a GO-reinforced matrix showed the best results, indicating its possible application as a second layer in multilayered armor systems.
Collapse
|
9
|
Ubim Fiber (Geonoma baculífera): A Less Known Brazilian Amazon Natural Fiber for Engineering Applications. SUSTAINABILITY 2021. [DOI: 10.3390/su14010421] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The production of synthetic materials generally uses non-renewable forms of energy, which are highly polluting. This is driving the search for natural materials that offer properties similar to synthetic ones. In particular, the use of natural lignocellulosic fibers (NLFs) has been investigated since the end of 20th century, and is emerging strongly as an alternative to replace synthetic components and reinforce composite materials for engineering applications. NLFs stand out in general as they are biodegradable, non-polluting, have comparatively less CO2 emission and are more economically viable. Furthermore, they are lighter and cheaper than synthetic fibers, and are a possible replacement as composite reinforcement with similar mechanical properties. In the present work, a less known NLF from the Amazon region, the ubim fiber (Geonoma bacculifera), was for the first time physically characterized by X-ray diffraction (XRD). Fiber density was statistically analyzed by the Weibull method. Using both the geometric method and the Archimedes’ technique, it was found that ubim fiber has one of the lowest densities, 0.70–0.73 g/cm3, for NLFs already reported in the literature. Excluding the porosity, however, the absolute density measured by pycnometry was relatively higher. In addition, the crystallinity index, of 83%, microfibril angle, of 7.42–7.49°, and ubim fiber microstructure of lumen and channel pores were also characterized by scanning electron microscopy. These preliminary results indicate a promising application of ubim fiber as eco-friendly reinforcement of civil construction composite material.
Collapse
|
10
|
Dynamic Mechanical Analysis of Thermally Aged Fique Fabric-Reinforced Epoxy Composites. Polymers (Basel) 2021; 13:polym13224037. [PMID: 34833335 PMCID: PMC8624808 DOI: 10.3390/polym13224037] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/10/2021] [Accepted: 11/13/2021] [Indexed: 12/04/2022] Open
Abstract
Dynamic mechanical analysis (DMA) is one of the most common methods employed to study a material’s viscoelastic properties. The effect of thermal aging on plain epoxy and a fique fabric-reinforced epoxy composite was investigated by comparing the mass loss, morphologies, and DMA properties of aged and unaged samples. In fact, thermal aging presents a big challenge for the high-temperature applications of natural fiber composites. In this work, both plain epoxy and fique fabric-reinforced epoxy composite were found to have different molecular mobility. This leads to distinct transition regions, with different changes in intensity caused by external loadings from time-aging. Three exponentially modified Gauss distribution functions (EMGs) were applied to loss factor curves of fique fabric-reinforced epoxy composite and plain epoxy, which allowed identifying three possible mobility ranges. From these results it was proposed that the thermal degradation behavior of natural fibers, especially fique fiber and their composites, might be assessed, based on their structural characteristics and mechanical properties.
Collapse
|
11
|
Souza ERS, Weber RP, Monteiro SN, Oliveira SDS. Microstructure Effect of Heat Input on Ballistic Performance of Welded High Strength Armor Steel. MATERIALS 2021; 14:ma14195789. [PMID: 34640186 PMCID: PMC8510201 DOI: 10.3390/ma14195789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 09/27/2021] [Accepted: 09/27/2021] [Indexed: 11/16/2022]
Abstract
The effect of two different heat inputs, 1.2 and 0.8 kJ/ mg, on the microstructure associated with a welded high hardness armor (HHA) steel was investigated by ballistic tests. A novel way of comparing the ballistic performance between fusion zone (FZ), heat-affected zone (HAZ), and base metal (BM) of the HHA joint plate was applied by using results of the limit velocity V50. These results of V50 were combined with those of ballistic absorbed impact energy, microhardness, and Charpy and tensile strength revealing that the higher ballistic performance was attained for the lower heat input. Indeed, the lower heat input was associated with a superior performance of the HAZ, by reaching a V50 projectile limit velocity of 668 m/s, as compared to V50 of 622 m/s for higher heat input as well as to both FZ and BM, with 556 and 567 m/s, respectively. Another relevant result, which is for the first time disclosed, refers to the comparative lower microhardness of the HAZ (445 HV) vs. BM (503 HV), in spite of the HAZ superior ballistic performance. This apparent contradiction is attributed to the HAZ bainitic microstructure with a relatively greater toughness, which was found more determinant for the ballistic resistance than the harder microstructure of the BM tempered martensite.
Collapse
Affiliation(s)
| | - Ricardo Pondé Weber
- Department of Materials Science, Military Institute of Engineering—IME, Rio de Janeiro 22290-270, Brazil;
| | - Sergio Neves Monteiro
- Department of Materials Science, Military Institute of Engineering—IME, Rio de Janeiro 22290-270, Brazil;
- Correspondence: or
| | - Suzane de Sant’Ana Oliveira
- Department of Inorganic Chemistry, Federal University of Rio de Janeiro—UFRJ, Rio de Janeiro 21941-909, Brazil;
| |
Collapse
|