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近年来高速火焰喷涂取得了飞速的发展，尽管热喷涂市场上的多种 ＨＶＯＦ系统结构各异，但对系统的性能要求是一致的，即：在有限的热量条件下，使喷涂材料达到尽可能高的速度以获得结构致密的涂层，而涂层材料本身不发生相变或氧化。 ＨＶＯＦ的现有模式几乎都是以燃烧室或加速喷管内高速焰流的稳定燃烧作为系统设计的理论模型，然而随着ＨＶＯＦ技术的不断发展；我们面临着两个问题迫切有待于解决：（１）颗粒速度倒底能被加速到多大；（２）颗粒速度的不断提高对涂层性能有何影响。采用燃料燃烧作为动力源对喷涂粉末同时加热和加速，这种方法使得气流在加速的同时付出了能焓和压力共同下降的代价。气流和喷涂粒子之间的相互作用将直接对喷涂粉末的沉积效率、涂层结构、组成和性能产生影响。ＨＶＯＦ的进一步发展是否存在技术和经济上的限制，这些问题都将在本文中讨论，尤其是本文将介绍利用专门设计的实验喷枪而得到的实验结果，其燃烧室压力能达到１０００ＰＳＩ（７０ＭＰａ），正因如此，高速运动的粉末粒子的加热性以及其它性能都受到影响。
In recent years, the rapid development of high-speed flame spraying has achieved rapid development. Although many HVOF systems in the thermal spraying market have different structures, the performance requirements of the system are consistent. That is, under the limited heat conditions, High speed to obtain a dense structure of the coating, the coating material itself does not undergo phase change or oxidation. However, with the continuous development of HVOF technology, we have to face two problems that are urgently needed to be solved: (1) The current model of HVOF is based on the theory of stable combustion of high- ) How fast the particle velocity can be accelerated; and (2) how the particle velocity affects the performance of the coating. The use of fuel combustion as a source of power to spray powder while heating and acceleration, this method makes the air flow while accelerating the enthalpy and pressure to pay the price of the common decline. The interaction between the gas flow and the spray particles will have an immediate effect on the deposition efficiency, coating structure, composition and properties of the spray powder. There are technical and economic limitations on the further development of HVOF, which are all discussed in this paper. In particular, this paper presents experimental results using a specially designed test gun with a chamber pressure of 1000 PSI (70 MPa) Because of this, the heating of powder particles moving at high speeds and other properties are affected.