木材气体保护摩擦焊接机理与工艺的实验研究

Although our country is a big country in manufacture, our country is not great power country. It is great significance for realizing the connotation of development, transformation of development and spanning development to improve product quality, reduce product cost, innovate and develop of high-end technology. Friction welding technology has been widely used in aerospace. Wood welding is a mechanical friction process allowing the assembly of wood without any adhesives. It is environmental friendly and non-toxic wood adhesives technology. The carbonization is the focus of present research, front subject and the difficulties with low intensity, not yet very good solution. In this project, wood gas protection friction welding test system was set up. The wood (Nagkassar, Rosewood, Cedar, Pine and Cottonwood, etc.) is used in the friction welding for the samples welded under different welding parameters in gas (air, N2, Ar, etc) protection. Friction welding interface characteristic parameters such as temperature, tribological characteristics, bond strength and the mechanical properties of melting zone and heat affected zone interface are tested. The formation mechanism and evolution of the micro structure and chemical composition of welding interface are analyzed. The corresponding mathematical models are established. The bonding mechanism of wood gas protection friction welding interface and multi-factor synergism mechanism are revealed. The friction welding process parameters are optimized. A new method of wood friction welding to improve the welding interface strength is developed. The project will solve the problem of low interface strength by reducing the carbonized degree of friction welding interface.

在我国从“制造大国”向“制造强国”迈进的关键时期，提高产品质量、降低产品成本、创新发展高端技术产业对实现跨越式发展具有重要意义。摩擦焊接技术在航空航天领域已得到广泛应用。木材摩擦焊接是不需任何胶黏剂的、环境友好的、无毒的木材粘结技术，其焊接界面炭化导致强度低的缺点，是木材摩擦焊接研究的前沿、热点和难点，至今尚未有效解决。本项目首先搭建木材气体保护摩擦焊接试验系统，在空气、N2、Ar等不同气体环境下，制备木材（铁力木、紫檀木、楠木、松木和杨木等）摩擦焊接样品，测试摩擦焊接界面温度、摩擦学特征、粘结强度以及熔化区、热影响区的力学性能等界面特征参数，分析焊接界面的微观结构、化学成分形成和演化规律，建立焊接工艺参数与界面特性的数字表征建模，揭示焊接界面的粘结机理以及多因素协同作用机制，进一步优化工艺，提出改善焊接界面强度的木材摩擦焊接新方法，通过降低摩擦焊接界面炭化程度，解决界面强度低的难题。

创新发展高端技术产业，节约能源，加强环境保护，是当今社会发展的主题之一，关系到国家的长远利益。. 木材摩擦焊接，是一种不需任何胶黏剂的，通过机械摩擦实现木材粘结的环境友好的、无毒的技术。本文设计并搭建了木材摩擦焊接实验装置，研究了焊接工艺参数、木材参数和界面介质对焊接界面摩擦力、压力和温度的影响规律。结果表明，焊入速度对界面压力和摩擦力有显著影响；木材含水率升高会降低焊接界面摩擦力和压力；纤维角度的增大会提高焊接界面摩擦力、压力和温度；在焊接界面引入葡萄糖和松香后，焊接界面强度会提升，为进一步的木材摩擦焊接机理及工艺研究提供了理论和技术基础。. 作为环保材料，木材也被用来制造水润滑轴承。铁力木具有很好的自润滑作用，曾经广泛应用于海上船舶艉轴承。但是，铁力木生长缓慢，资源日渐缺乏，价格昂贵。本文研究了铁力木、蚬木等浸泡水、PAO油、桐油和壳牌润滑油后的摩擦学行为，通过树脂抽提处理和水抽提处理，研究木材及其改性后摩擦学行为及水润滑机理。蚬木可能成为替代铁力木的水润滑材料，这也为进一步仿生水润滑轴承材料的设计开发提供了理论支撑。. 在本项目的支持下，发表SCI检索论文3篇，授权国家发明专利2件，申请国家发明专利1件。