EFFECT OF HEAT TREATMENT AND CROSS SECTION ON THE CRASHWORTHINESS OF 51CRV4 SPRING STEEL

Öz

In this study, the 51CrV4 spring steel was used as crash box material and its crashworthiness was investigated. Crash boxes with cylinder and rectangular geometries were designed in SolidWorks and nonlinear finite-element analysis was performed in HyperWorks software. In addition, 51CrV4 spring steel was subjected to three different heat treatments and their mechanical properties were determined by tensile and hardness tests. The crashworthiness of structure was evaluated taking into account the total energy absorbed, peak force and the specific energy absorbed. It has been observed that heat treatment and geometric changes have a serious impact on crashworthiness.

Anahtar Kelimeler

• Thin-Walled Tubes,Crashworthiness,Mechanical Strength,Crash Box

51CrV4 Yay Çeliğinde Isıl Işlem ve Kesit Geometrisinin Çarpışma Dayanıklılığı Üzerine Etkisi

Öz

Bu çalışmada, 51CrV4 yay çeliği çarpışma kutusu malzemesi olarak kullanılmış ve çarpışma dayanıklılığı araştırılmıştır. Kare ve silindir kesit geometrisine sahip çarpışma kutuları SolidWorks programında tasarlanmış olup lineer olmayan sonlu elemanlar analizi ise HyperWorks yazılımında gerçekleştirilmiştir. Buna ek olarak, 51CrV4 çelik malzemesi 3 farklı ısıl işleme maruz bırakılarak mekanik özellikleri çekme ve sertlik testleri ile belirlenmiştir. Belirlenen mekanik özelliklere sahip yapının çarpışma dayanıklılığı, emilen özgül enerji, maksimum çarpışma kuvveti ve emilen toplam enerji hesaba katılarak değerlendirilmiştir. Isıl işlem uygulamasının ve kesit geometrisinin çarpışma dayanıklılığı üzerinde ciddi bir etkisi olduğu gözlemlenmiştir.

Anahtar Kelimeler

• Ince-Cidarlı Tüpler,Çarpışma Dayanıklılığı,Mekanik Dayanım,Çarpışma Kutusu

Kaynakça

1. 1. Alavi Nia, A. and Parsapour, M. (2014). Comparative analysis of energy absorption capacity of simple and multi-cell thin-walled tubes with triangular, square, hexagonal and octagonal sections. Thin-Walled Structures, 74, 155-165. doi:10.1016/j.tws.2013.10.005.
2. 2. Bambach, M., Conrads, L., Daamen, M., Güvenç, O, and Hirt, G. (2016). Enhancing the crashworthiness of high-manganese steel by strain-hardening engineering, and tailored folding by local heat-treatment. Materials & Design, 110, 157-168. doi:10.1016/j.matdes.2016.07.065.
3. 3. Campana, F. and Pilone, D. (2009). Effect of heat treatments on the mechanical behaviour of aluminium alloy foams. Scripta Materialia, 60(8), 679-682. doi:10.1016/j.scriptamat.2008.12.045.
4. 4. Conrads, L., Conrad, L. and Hirt G. (2017). Increasing the energy absorption capacity of structural components made of low alloy steel by combining strain hardening and local heat treatment. International Conference on the Technology of Plasticity, ICTP 2017, 17-22 September 2017, Cambridge, United Kingdom.
5. 5. Karagöz, S. and Yıldız, A. R. (2017). Comparison of recent metaheuristic algorithms for crashworthiness optimisation of vehicle thin-walled tubes considering sheet metal forming effects. Int. J. Vehicle Design, Vol. 73, Nos. 1/2/3, 2017. doi:10.1504/IJVD.2017.082593
6. 6. Liang, C., Wang, C. J., Nguyen, V. B., English, M. and Mynors, D. (2017). Experimental and numerical study on crashworthiness of cold-formed dimpled steel columns. Thin-Walled Structures, 112, 83-91. doi:10.1016/j.tws.2016.12.020.
7. 7. Millett, J., Bourne, N. and Edwards, M. (2004). The effect of heat treatment on the shock induced mechanical properties of the aluminium alloy, 7017. Scripta Materialia, 51(10), 967-971. doi:10.1016/j.scriptamat.2004.07.020.
8. 8. Nakazawa, Y., Tamura, K., Yoshida, M., Tagaki, K. and Kano, M. (2005) Development of crash-box for passenger car with high capability for energy absorption, VIII. International Conference on Computational Plasticity, Barcelona, Spain.

9. 9. N Nasir, H., Srinivasa Prakash, R., Yendluri V. and Daseswara, R. (2017). Comparative Study Of Trigger Configuration For Enhancement Of Crashworthiness Of Automobile Crash Box Subjected To Axial Impact Loading. Procedia Engineering, 173, 1390-1398. doi: 10.1016/j.proeng.2016.12.198
10. 10. N Nasir, H. (2015). Automobile Crash Box Design Improvement Using HyperStudy. India Altair Technology Conference. Hyundai Motor India Engineering Pvt. Ltd. Survey No. 5/2,5/3. Opp. Hitech City Railway Station, Izzatnagar, Hyd – 84.
11. 11. Öztürk, İ. and Kaya, N. (2008). Otomobil Ön Tampon Çarpişma Analizi Ve Optimizasyon, Uludağ Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi, Cilt 13, Sayı 1.
12. 12. Tran, T., Hou, S., Han, X. and Chau, M. (2015). Crushing analysis and numerical optimization of angle element structures under axial impact loading. Composite Structures, 119, 422-435. doi:10.1016/j.compstruct.2014.09.019.
13. 13. Xie, S., Yang, W., Wang, N. and Li, H. (2017). Crashworthiness analysis of multi-cell square tubes under axial loads. International Journal of Mechanical Sciences, 121, 106-118. doi:10.1016/j.ijmecsci.2016.12.005.
14. 14. Yao, S., Xing, Y. and Zhao, K. (2017). Crashworthiness analysis and multiobjective optimization for circular tubes with functionally graded thickness under multiple loading angles. Advances in Mechanical Engineering, 9(4). doi:10.1177/1687814017696660.
15. 15. Yıldız, A. R., Kurtuluş, E., Demirci, E., Yıldız, B. S. and Karagöz, S. (2016). Optimization of thin-wall structures using hybrid gravitational search and Nelder-Mead algorithm. Materials Testing, Vol. 58, No. 1, pp. 75-78. https://doi.org/10.3139/120.110823.