Next we present briefly two mechanisms of energy accumulation in solids under IPEB and IPIB irradiation, that determinate the following non-linear long-range effects: (1) IPEB brittle fracture of ionic crystals (IC) [5]; (2) IPIB damages and hardening at high depths in metals.
1. The main results on brittle fracture for all classes of solids under IPEB (0.2–15 MeV, 2–60 ns, 1–400 J/cm2/pulse) response are presented in [5]. Except IC its mechanism is thermal shock. The unique characteristics of IC fracture indicate on the main role of ES excitation. This fracture is represented by a time sequence of three stages [5]: Initiation, determined by the processes of accumulation of irradiation energy in generated non-equilibrium non-ideal electron — hole plasma with concentration n ~1017–1018 cm–3. The dependence of general plasma energy density E from n has the deep minimum with n ~1022 cm–3 , that confirms the existence of phase transformation of the first order with the nucleation of drops of electron-hole condensed phase (EHCP), where E is ~103 J/cm3 , that is closed to IC binding energy density. Intense electron-hole recombination in EHCP drops created non-stable clusters of the Frenkel pair defects (FDP). The first spontaneous FDP cluster burst creates thermal and elastic waves that initiate other shot-range drop bursts with generations of microcracks. At the second stage (Propagation) the fracture front propagates with longitudinal sound velocity. At the third stage (Formation) the main crack is created in result of the coalescence of microcracks and destroys the sample. The general fracture path of this fracture is 1–2–3–4–22–24–25–32, where b 32 is a destroyed sample. The detected unique luminescence (b23) [18] and our calculations confirmed EHCP existence [5].
FIGURE 1. Scheme of energy
transformation in solids exposed to radiation fluences
2. Under proton-carbon IPIB metals and alloys irradiation (0.2–0.6 MeV, 10–7 s, 1–40 J/cm2/pulse) we observed the following stable long-range effects in non-irradiated region: (1) anomalous microhardness increasing of Hz=(1.5–3)×Ho and wear resistance Iz=(1.2–2.5)×I0 (Ho, Io are their initial magnitudes for non-irradiated samples) at high depths z=(40-200)×R0, (R0~l mm is ion beam range); (2) four layers formation with different character of residual deformation states [1, 3, 4, 7]; (3) redistribution of alloy elements in steels [1, 6]. Analyze of the influence of ion implantation, intense pulsed laser, ion and electron irradiations proved SW main contribution. We proposed this phenomena mechanism [3, 8]. SW with 1–10 GPa initial pressure was detected [20] and calculated [1, 4]. Early pulsed laser response on semiconductors shown the most intense defect generation in SW front (SWF) formation region where SW pressure gradient was maximum [19]. The three above mentioned effects are induced by SW energy redistribution over target depth with SW maximum energy transfer to the lattice in SWF region and intense Frenkel pair defects generation. Then the flow of interstitials to dislocations and different dislocation reactions, observed in our experiments [1–4], caused the hardening at high depths. We notice two possible paths: (1) 1–2–4–30–6–8–9–10–11–14–16–17–20–15–32–33; (2) 1–2–4–26–14–16–17–20–15–32–33. Calculations, made with using our kinetic model of hardening, are in good agreement not only with our experimental results, but also with US [21] and France [22] last investigations.
CONCLUSIONs
The proposed scheme may be used not only under irradiation, but also for mechanical, thermal and explosives responses. It is not pretended as the general and universal one at all. Every its block may be added with details for a good phenomenon interpretation. For example, the detail scheme of solid hardening in SW field is included 22 blocks [2].We have the method for variation of energy redistributions on different channels and may realize the monitoring for radiation processes and their optimal management. IPEB and IPIB processes and effects have the following general features: (1) They are determined by ES and AS collective excitation, nonlinear, i. e. observed at intensities and fluences; (2) They are depended on the combined action of the generated intense radiation, thermal, and mechanical fields, that cause essentially nonequilibrium phase transitions of the first and second orders to occur; (4) They proceed at high rates with characteristic times of 10–8–10–5 s (5) their long-range effects are related to the specific of elastic, elastoplastic and SW action on the structure. The limited spectrum of properties of solids materials is the main reason, why the progress in developing the technology of processing is so slow. IPEB and IPEB ensure successful modification of the already existing properties and create some new unique properties for materials with improvement wear, corrosion and erosion resistance, fatigue strength, fracture and cleaning. Good results have been achieved by combining thermo-chemical methods, ion implantation, and intense irradiation [8, 12]. Also IPEB is used in special acoustic wave generation for diagnostic of characteristics unknown materials [15]. Today ablation plasma deposition on special substrates is used for synthesis of for diamond-like coatings [23, 24] and thin films as new unique materials for microsystems of electronics (see references in [2–4]).
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