硬度对装甲钢板抗弹性能的影响

借助用53式7．62mm WO-109C穿甲燃烧弹垂直撞击10mm厚、硬度为HRC44－56的Cr-Ni-Mo装甲钢板的穿甲试验研究了高硬度及超高硬度状态下硬度对装甲钢板抗弹性能的影响。观察分析弹坑形貌发现,装甲钢板材料力学性能的改变导致了穿甲机理的变化。一方面,硬度升高,增加弹丸开坑所消耗的能量,提高弹丸消耗的塑性扩孔功,且当硬度超过一定值时,弹丸可能发生破碎,从而有利于抗弹性能的提高。另一方面,硬度升高,导致绝热剪切临界失稳应变降低,易诱发冲塞破坏,而且塑性与韧性降低,可能导致背面盘状崩落破坏,从而使抗弹性能下降。在本试验弹靶体系下,上述两方面相反作用的结果导致装甲钢板背面强度极限基本上不随硬度变化而改变。     

高强度装甲钢中绝热剪切破坏研究

为了研究高强度装甲钢的穿甲破坏机理，采用１２．７ｍｍ弹道枪垂直射击１５ｍｍ厚的Ｍｎ－Ｃｒ－Ｎｉ－Ｍｏ－Ｂ高强度装甲钢板，弹丸速度在３５０～５００ｍ／ｓ内变化，分析了绝热剪切带的产生及其对冲塞穿甲的作用。试验结果表明，当弹靶参数一定时，高强度钢板中易发生绝热剪切导致的冲塞穿甲，由微观组织和硬度测试证明绝热剪切带是一种转变带。转变带内的裂纹和沿转变带扩展的裂纹对装甲的钢的破坏影响极大。     

装甲钛合金的研究与应用现状

综述了国内外装甲钛合金的研究现状,主要论述了抗弹性能及抗毁伤机理、附加装甲结构单元技术、应用基础研究等;介绍了抗弹性能考核评价及板材验收规范,主要包括抗弹性能考核评价方法、抗弹性能指标体系建立、板材验收标准制定情况等。通过对装甲钛合金应用现状和发展趋势的分析,加深人们对装甲钛合金材料和应用技术的理解,推动装甲钛合金材料的工程化应用。在进一步论述装甲钛合金应用现状的基础上,提出了未来装甲钛合金研究发展趋势。     

低成本XRF001钛合金抗弹性能研究

研究了一种新型装甲用低成本钛合金XRF001的组织与性能,重点对其抗弹性能进行了测试,分析了抗弹机理。结果表明：普通退火态XRF001钛合金板材的强度、塑性、硬度和冲击韧性匹配良好,抗弹性能与ATI425-MOD钛合金相当,优于ATI425钛合金。XRF001钛合金在不同热处理状态下的组织不同,抗弹性能也不同,普通退火态下的抗弹性能优于双重退火态。经普通退火后,XRF001钛合金中形成的细小板条及片层状组织能够改变绝热剪切带走向,改变裂纹扩展路径,消耗更多的能量,有利于提高抗弹性能。     

500HB级装甲钢抗弹性能和工艺性能研究

500HB级别装甲钢因其具有独特抗弹性能、折弯成型性能,成为新一代轮式装甲车车身主要材料。本文针对南钢研制的500HB装甲钢,研究4～30 mm厚钢板化学成分设计、显微组织类型、抗弹极限、折弯极限。     

两种不同强塑性薄钢板抗弹性能的试验和数值模拟

 利用51B式7.62mm手枪弹对不同强度和塑性的薄钢板进行枪击试验,采用ANSYS/LS-DYNA软件对试验过程进行数值模拟,对试验和数值模拟过程的钢板破坏形貌、背凸高度、残余弹丸长度等宏观形貌进行比较。结合抗弹过程中弹丸和钢板消耗的能量,分析了强度和塑性对钢板抗弹性能的影响。结果表明：尽管两种钢板的抗拉强度和断后伸长率差异较大,但其抗51B式7.62mm手枪弹性能相当。试验和数值模拟结果吻合较好,模拟方法能够正确地反映弹丸冲击靶板过程。因较高强度钢板使弹丸变形消耗的能量大于较低强度钢板,塑性较好钢板本身变形消耗的能量大于较低塑性钢板,从而解释了两种钢板抗弹性能相当的试验结果。     

通过织构化来改善钢的强度

美国军用材料和军械研究中心的研究已经证明,装甲钢板的织构(优选的结晶位向—晶体定向)可以颇大地提高它的抗射弹性。研究结果表明,织构钢的抗弹道穿透能力比同样硬度值的无定向织构钢高25%。研究是在经815℃轧制的厚度为0.5吋(1.3厘米)的装甲钢板上进行的,因此得到织构组织。轧制的厚度压下量范围从60%到90%,其相应的织构强度为3.75—9.05。试     

国外均质轧制装甲钢板的生产现状及发展方向

简要介绍了装甲防护的基本原理和国外传统装甲钢的历史沿革,描述了现代装甲钢板的技术特点,列举了国外五个国家装甲钢板的系列品种、设计思路及主要技术指标,指出了国外装甲板的发展方向是高硬度、轻量化、纯净化,并将在民用领域得到广泛应用。     

搪瓷用冷轧薄钢板的生产

搪瓷用钢板需具有良好的密着性、抗搪烧变形性、抗鳞性等特殊的搪烧工艺性能。我国日用搪瓷用冷轧薄板为非搪瓷专用板,鳞爆、气泡、弹点等缺陷时有发生。国外搪瓷板已系列化,生产工艺日趋完善。     

弹丸高速冲击条件下高强度钢板抗弹性能

为了研究弹丸高速冲击条件下不同洁净度的40CrNi2Mo钢板的抗弹性能,利用12.7 mm穿甲燃烧弹对抗拉强度分别为800和1 200 MPa级的钢板进行抗弹性能测试。通过观察不同强度钢板出现的损伤形貌,评定背面强度极限,分析了穿甲机制。结果表明:抗拉强度为800 MPa级的钢板在弹丸冲击过程中以塑性扩孔方式侵彻,抗弹性能随着强度升高而提高,与洁净度关系不大。抗拉强度为1 200 MPa级的钢板,弹丸冲击过程中因钢板较低的绝热剪切临界失稳应变而出现绝热剪切;由于塑韧性较低,低洁净度钢板阻止绝热剪切引发裂纹扩展的能力较弱,因此形成与绝热剪切相关的裂纹,导致抗弹性能降低;高洁净度钢板抗弹性能相对较高,因背面出现剪切裂纹而失效,此裂纹与绝热剪切无关。     

生产工艺对粉冶热轧钼板硬度和弯曲性能的影响

研究了生产工艺参数对粉冶轧钼板材的硬度和弯曲性能的影响试验结果表明，热轧钼板材的硬度和弯曲性能，主要受轧制变形量，加热温度等工艺参数的影响；粉末坯条的成型压力对最终板材硬度和弯曲角无影响，控制适当的钼板加工工艺，可获得理想的板材硬度，弯曲角等综合性能。     

Development and Production of HSLA Wear-Resistant Steel

In this paper,the development and production of Ti-Cr-B microalloyed NM400 wear-resistant steel were discussed,along with the influence of heat treatment process parameters on the mechanical properties.The continuous cooling transformation behavior of steel was investigated by means of thermal simulator.Effects of austenitizing temperature on microstructures and properties of steel were studied.Martensite laths evolution,carbide transformation and precipitation behavior were observed by TEM.The wear-resistance of steel was compared with other similar steels.The results show that the steel has high strength and hardness,great low-temperature toughness and wear-resistance.The tensile strength is more than 1300 MPa,and the hardness is in the range of 390-430 HB.Due to the good hardenability,the steel has a uniform hardness distribution on the surface and thickness direction.The plate shape,cold bending property and weldability of the product can meet the user’s requirement.     

Effect of Capping Front Layer Materials on the Penetration Resistance of Q&T Steel Welded Joints Against 7.62-mm Armor-Piercing Projectile

In the present investigation, an attempt has been made to study the effect of capping front layers on the ballistic performance of shielded metal arc-welded armor steel joints which were fabricated with a chromium carbide-rich hardfaced middle layer on the buttered/beveled edge. Two different capping front layer materials were chosen for achieving better ballistic performance, namely, low hydrogen ferritic (LHF) and austenitic stainless steel (SS) fillers. On the other hand, the bottom layers are welded with SS filler for both joints. The consequent sandwiched joint served the dual purpose of weld integrity and penetration resistance of the bullet. It is observed that the penetration resistance is due to the high hardness of the hardfacing layer on the one hand and the energy-absorbing capacity of the soft backing SS weld deposits on the other hand. The complementary effect of layers successfully provided resistance to the projectile penetration. On a comparative analysis, the joint fabricated using the LHF filler capping front layer offered superior ballistic performance with respect to depth of penetration. This is mainly due to the presence of acicular ferrite along the bainitic structure in the LHF capping front layer, which caused a shallow hardness gradient along the weld center line.     

Correlation of Microstructure and Ballistic Performance of Multilayered Zr-based Amorphous Surface Composites Fabricated by High-Energy Electron-Beam Irradiation

In this study, multilayered, Zr-based amorphous surface composites were fabricated by high-energy electron-beam irradiation; the correlation of their microstructure, hardness, compressive properties, and fracture properties with ballistic performance was investigated. The mixture of Zr-based amorphous powders and LiF + MgF₂ flux powders was deposited on a pure Ti substrate or a plain carbon steel substrate, and then an electron beam was irradiated on this powder mixture to fabricate a one-layered surface composite. The multilayered surface composite was fabricated by an irradiating electron beam several times again onto the powder mixture deposited on the one-layered surface composite. The microstructural analysis results indicated that a small amount of fine crystalline particles was distributed homogeneously in the surface composite layer. Because the surface composite layers absorbed the ballistic impact energy by forming many cracks or microcracks, the surface composite plates were not perforated during the ballistic impact test. On the one hand, in the surface composite without containing ductile β phases, the composite layer was cracked completely and fallen off from the substrate. On the other hand, a small amount of fragmentation was found in the impacted area of the composite containing β phases because it had the sufficient hardness and fracture toughness simultaneously for effectively blocking the traveling of a projectile, thereby improving ballistic performance.     

改善TA1板材硬度的研究

为解决TA1板材硬度(HRB)超标的问题,本文作者对影响TA1板材硬度的一些因素如TA1杂质含量及其均匀性、轧制变形量、退火温度进行了研究,发现TA1板材的硬度首先取决于O、N、C等杂质含量的高低及分布的均匀性,同时加大轧制变形量会提高板材的硬度,而提高退火温度可降低板材硬度。最终得出结论:要控制TA1板材HRB≤80,就应控制其O≤0.10%,N≤0.02%,C≤0.03%,而板材退火温度控制在750℃为好,此时冷轧变形量达到40%也不会出现硬度超标的问题。     

钛钢复合板弯曲过程的扫描电镜原位观察

为了研究钛钢复合板在弯曲过程中的断裂行为,利用扫描电镜原位观察了爆炸和爆炸-轧制两种工艺生产的钛钢复合板在弯曲过程中裂纹的萌生和扩展.结果表明:外弯过程裂纹萌生的角度小于内弯过程,钛钢复合板内弯比外弯具有更强的抗裂纹产生能力.在爆炸钛钢复合板的弯曲过程中,裂纹主要在波头的界面结合处和漩涡中心处萌生;在爆炸-轧制钛钢复合板的弯曲过程中,裂纹在Ti-Fe金属间化合物硬块界面处萌生.产生裂纹的主要原因爆炸钛钢复合板的波头界面结合处和漩涡中心处、爆炸-轧制钛钢复合板的界面块状Ti-Fe金属间化合物具有较高的硬度,在变形的过程中难以协调变形.      

热处理工艺对高C-Cr高强耐磨钢组织和性能的影响

设计了一种高C-Cr高强耐磨钢,测试了末端淬透性,研究了不同热处理工艺对微观组织演变和性能的影响,测试了力学性能和耐磨损性能,利用SEM和TEM表征了微观组织。试验结果表明,随距离淬火端距离的增大,试验钢的硬度呈现单调递减的趋势,0~2.5 cm为硬度平缓降低阶段,布氏硬度在63~65HRC的区间。马氏体淬火+回火处理后,试验钢基体组织主要为马氏体板条,板条尺寸大小不一。经贝氏体等温淬火处理后,贝氏体板条相互平行,板条尺寸平均。贝氏体板条间存在薄膜状的残留奥氏体,贝氏体板条内部存在长度为100~150 nm的碳化物析出相,析出相与贝氏体板条呈60°取向排列。磨损过程中,达到800转时,马氏体基体试验钢失重168 mg,贝氏体基体失重192 mg,增加了14.28%,马氏体基体的耐磨损性能更高。而贝氏体基体的力学性能却明显高于马氏体基体,屈服强度达到1 955 MPa,抗拉强度达到了2 485 MPa,伸长率仍然达到了7%。     

模具用经济型P20板材生产实践

根据用户特定需求,在P20的基础上研发了经济型P20塑料模具用钢板。整个试制过程控制平稳,钢水洁净度较高,成品钢板表面质量良好。成品试样检测结果表明,在热轧和控轧两种轧制工艺下的钢板试样硬度在36.5~40.3HRC之间,均符合设计要求,金相组织为F+P+B,控轧工艺试样硬度高于热轧工艺试样,且控轧工艺试样组织更加细小,回火处理后硬度均有所降低,组织更加均匀。     

Correlation of dynamic torsional properties with adiabatic shear banding behavior in ballistically impacted aluminum-lithium alloys

The present study is concerned with a correlation between dynamic deformation properties obtained from the dynamic Kolsky bar test with the adiabatic shear banding behavior developed in Al-Li alloys upon ballistic impact, and then with the ballistic performance. The selected materials were a 2090 Al-Li alloy, a WELDALITE 049 alloy, and a 7039 Al alloy, to allow a comparative study of different strengths and microstructures. After the ballistic impact testing, the amount and the distribution of adiabatic shear bands were examined using optical and scanning electron microscopes. In the front side of the impacted area, many thin delaminated sheets and a large amount of fragmentation were observed in the 2090 alloy and the WELDALITE alloy, respectively. Near the impacted region, a large amount of plastic flow also existed, and adiabatic shear bands were hardly observed in the 2090 and the WELDALITE alloys, whereas they easily formed in the 7039 alloy. Since adiabatic shear bands usually deteriorate the impact resistance of target materials, the ballistic performance of each alloy was discussed by comparing the adiabatic shear banding behavior with microstructure, strength level, and dynamic torsional properties.