Publication: Namlularda atış ömrünü etkileyen sert krom ve oksidasyon kaplama parametrelerinin karşılaştırılması
Abstract
NAMLULARDA ATIŞ ÖMRÜNÜ ETKİLEYEN SERT KROM VE OKSİDASYON KAPLAMA PARAMETRELERİNİN KARŞILAŞTIRILMASITürkiye silah üretimi konusunda dünyada önemli bir konuma sahiptir. Özellikle av ve spor alanında kullanılan silahlar teknoloji ve rekabetin gelişmesi ile daha yüksek kalite ve ömre sahip ürünler haline gelmektedir. Silahın ömrünü belirleyen en önemli birleşeni namludur. Namlunun ömrü silahın ömrünü belirlerken bir silah üreticisinin de kalitesini göstermektedir.Namlu, ateşleme esnasında kuvvetli basınç ve sıcaklığa maruz kalmaktadır. Süregelen atış ile birlikte sürtünme, aşınma, korozyon ve basınca karşı yüksek mekanik özellik göstermesi gerekmektedir. Bu mekanik özellikleri yalnızca iyi bir tasarım değil, iyi bir malzeme ve bu malzemenin mekanik özelliklerini geliştirecek işlemler belirlemektedir. Gelişen teknoloji ile birlikte kullanıcılar, daha hafif daha uzun ömürlü namluları talep ederken klasik yöntemler yerine yeni yöntemler ile imalat yöntemleri geliştirilmektedir. Bu çalışmada, namlu çeliğinin yüzeyine kaplanan sert krom ve oksidasyon kaplama uygulamalarının namlu çeliğinin metalografik, mikro sertlik, yüzey pürüzlüğü, aşınma, korozyon, atış özelliklerine etkisi incelenmiştir. Araştırma çalışmaları AKKAR silah fabrikası Ar-Ge merkezinde ve Gebze Teknik Üniversitesi Malzeme Bilimi ve Mühendisliği bölümünde gerçekleştirilmiştir. Namlu malzemesi, SİJ METAL RAVNE firmasından üretilmiş ve ıslah edilmiş olarak alınarak kullanılmıştır.Namlu çeliğinin aşınma ve korozyon davranışlarını incelemek için numuneler hazırlanmış olup, yüzeyleri sert krom ve oksit kaplanmıştır. Aşınma deneylerinde aşındırıcı olarak iki farklı uç ve yük kullanılmıştır. Numunelerin korozyon davranışları, TS EN ISO 9227 standardına uygun tuz deneyi yapılarak gözlenmiştir. Metalografik incelemeler optik mikroskop ile gerçekleştirilmiştir. Namlu çeliğinin atış özelliklerini incelemek için iki adet namlu imal edilmiştir. Namlulardan bir tanesi oksidasyon, diğeri sert krom kaplanmıştır. Namlular tek bir süperpoze tüfeğine montajı yapılmış olup, atış sonrasında saçma dağılımı, namlulardan mermi çıkış hızları, namluların iç yüzey kalitesi tespit edilmiştir.Oksidasyon kaplanmış namlu, atış testleri sonrasında kurşun sıvanması, yüzey pürüzlülüğü, mermi çıkış hızı ve saçma dağılımı değerleri ile de sert kromdan daha üstün özellikler gösterdiği tespit edilmiştir.
COMPARISON OF HARD CHROME AND OXIDATION COATING PARAMETERS AFFECTING THE SHOOTING LIFE OF BARRELSTurkey has an important position in the world for weapon production. Weapons used especially in hunting and sports fields become products with higher quality and life with the development of technology and competition. The most important component that determines the life of the gun is the barrel. While the life of the barrel determines the life of the gun, it also shows the quality of a gun manufacturer.The barrel is exposed to strong pressure and heat during shooting. It must show high mechanical properties against friction, abrasion, corrosion and pressure with the ongoing shooting. These mechanical properties are determined not only by a good design, but also by a good material and processes which improve the mechanical properties of this material.While the developing technology demands lighter and longer lasting barrels, manufacturing studies are developed with new methods instead of classical methods.With the developing technology, the users demand lighter and longer lasting barrels, new manufacturing methods are developed instead of classical methods.In this study, the effects of hard chrome and oxidation coating applications on the surface of barrel steel on metallographic, micro hardness, surface roughness, abrasion, corrosion, shooting characteristics of barrel steel were researched. Research studies were carried out in AKKAR Weapon Factory R&D center and Gebze Technical University Materials Science and Engineering department. Barrel material was taken from SİJ METAL RAVNE company and used as improved.Samples were prepared to analyze the abrasion and corrosion behavior of barrel steel while its surfaces were coated with hard chromium and oxide. Two different tips and loads were used as abrasive in the abrasion tests. The corrosion behavior of the samples was observed by conducting salt tests in accordance with TS EN ISO 9227 standard. Metallographic analzyes were carried out with using an optical microscope. Two barrels were manufactured to analyze the shooting characteristics of barrel steel. One of the barrels was coated with oxidation, the other is with hard chrome. The barrels were mounted on the same superposition rifle, and the pellet distribution, bullet exit velocities from the barrels, and inner surface quality of the barrels were determined after shooting.It has been observed that the oxidation-coated barrel has better characteristics than hard chrome in terms of bullet plastering, surface roughness, bullet exit velocity and pellet dispersion after shooting tests
COMPARISON OF HARD CHROME AND OXIDATION COATING PARAMETERS AFFECTING THE SHOOTING LIFE OF BARRELSTurkey has an important position in the world for weapon production. Weapons used especially in hunting and sports fields become products with higher quality and life with the development of technology and competition. The most important component that determines the life of the gun is the barrel. While the life of the barrel determines the life of the gun, it also shows the quality of a gun manufacturer.The barrel is exposed to strong pressure and heat during shooting. It must show high mechanical properties against friction, abrasion, corrosion and pressure with the ongoing shooting. These mechanical properties are determined not only by a good design, but also by a good material and processes which improve the mechanical properties of this material.While the developing technology demands lighter and longer lasting barrels, manufacturing studies are developed with new methods instead of classical methods.With the developing technology, the users demand lighter and longer lasting barrels, new manufacturing methods are developed instead of classical methods.In this study, the effects of hard chrome and oxidation coating applications on the surface of barrel steel on metallographic, micro hardness, surface roughness, abrasion, corrosion, shooting characteristics of barrel steel were researched. Research studies were carried out in AKKAR Weapon Factory R&D center and Gebze Technical University Materials Science and Engineering department. Barrel material was taken from SİJ METAL RAVNE company and used as improved.Samples were prepared to analyze the abrasion and corrosion behavior of barrel steel while its surfaces were coated with hard chromium and oxide. Two different tips and loads were used as abrasive in the abrasion tests. The corrosion behavior of the samples was observed by conducting salt tests in accordance with TS EN ISO 9227 standard. Metallographic analzyes were carried out with using an optical microscope. Two barrels were manufactured to analyze the shooting characteristics of barrel steel. One of the barrels was coated with oxidation, the other is with hard chrome. The barrels were mounted on the same superposition rifle, and the pellet distribution, bullet exit velocities from the barrels, and inner surface quality of the barrels were determined after shooting.It has been observed that the oxidation-coated barrel has better characteristics than hard chrome in terms of bullet plastering, surface roughness, bullet exit velocity and pellet dispersion after shooting tests